Update field.rs

Removing the contract about the order of the field, and the
field id allocation.

.github/FUNDING.yml

@@ -1,12 +0,0 @@
-# These are supported funding model platforms
-
-github: fulmicoton
-patreon: # Replace with a single Patreon username
-open_collective: # Replace with a single Open Collective username
-ko_fi: # Replace with a single Ko-fi username
-tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
-community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
-liberapay: # Replace with a single Liberapay username
-issuehunt: # Replace with a single IssueHunt username
-otechie: # Replace with a single Otechie username
-custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

CHANGELOG.md

@@ -1,17 +1,3 @@
-Tantivy 0.11.3
-=======================
-- Fixed DateTime as a fast field (#735)
-
-Tantivy 0.11.2
-=======================
-- The future returned by `IndexWriter::merge` does not borrow `self` mutably anymore (#732)
-- Exposing a constructor for `WatchHandle` (#731)
-
-Tantivy 0.11.1
-=====================
-- Bug fix #729
-
-
 Tantivy 0.11.0
 =====================
 
@@ -23,19 +9,13 @@ Tantivy 0.11.0
 - API change around `Box<BoxableTokenizer>`. See detail in #629
 - Avoid rebuilding Regex automaton whenever a regex query is reused. #639 (@brainlock)
 - Add footer with some metadata to index files. #605 (@fdb-hiroshima)
-- Add a method to check the compatibility of the footer in the index with the running version of tantivy (@petr-tik)
-- TopDocs collector: ensure stable sorting on equal score. #671 (@brainlock)
-- Added handling of pre-tokenized text fields (#642), which will enable users to
-  load tokens created outside tantivy. See usage in examples/pre_tokenized_text. (@kkoziara)
-- Fix crash when committing multiple times with deleted documents. #681 (@brainlock)
-
+ 
 ## How to update?
 
-- The index format is changed. You are required to reindex your data to use tantivy 0.11. 
 - `Box<dyn BoxableTokenizer>` has been replaced by a `BoxedTokenizer` struct.
 - Regex are now compiled when the `RegexQuery` instance is built. As a result, it can now return
 an error and handling the `Result` is required.
-- `tantivy::version()` now returns a `Version` object. This object implements `ToString()`
+
 
 Tantivy 0.10.2
 =====================

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tantivy"
-version = "0.11.3"
+version = "0.11.0"
 authors = ["Paul Masurel <paul.masurel@gmail.com>"]
 license = "MIT"
 categories = ["database-implementations", "data-structures"]
@@ -13,7 +13,7 @@ keywords = ["search", "information", "retrieval"]
 edition = "2018"
 
 [dependencies]
-base64 = "0.11.0"
+base64 = "0.10.0"
 byteorder = "1.0"
 crc32fast = "1.2.0"
 once_cell = "1.0"
@@ -33,25 +33,27 @@ fs2={version="0.4", optional=true}
 itertools = "0.8"
 levenshtein_automata = {version="0.1", features=["fst_automaton"]}
 notify = {version="4", optional=true}
-uuid = { version = "0.8", features = ["v4", "serde"] }
+bit-set = "0.5"
+uuid = { version = "0.7.2", features = ["v4", "serde"] }
 crossbeam = "0.7"
-futures = {version = "0.3",  features=["thread-pool"] }
+futures = "0.1"
+futures-cpupool = "0.1"
 owning_ref = "0.4"
 stable_deref_trait = "1.0.0"
-rust-stemmers = "1.2"
+rust-stemmers = "1.1"
 downcast-rs = { version="1.0" }
-tantivy-query-grammar = { version="0.11", path="./query-grammar" }
+tantivy-query-grammar = { path="./query-grammar" }
 bitpacking = {version="0.8", default-features = false, features=["bitpacker4x"]}
-census = "0.4"
+census = "0.2"
 fnv = "1.0.6"
 owned-read = "0.4"
 failure = "0.1"
 htmlescape = "0.3.1"
 fail = "0.3"
+scoped-pool = "1.0"
 murmurhash32 = "0.2"
 chrono = "0.4"
-smallvec = "1.0"
-rayon = "1"
+smallvec = "0.6"
 
 [target.'cfg(windows)'.dependencies]
 winapi = "0.3"
@@ -62,10 +64,6 @@ maplit = "1"
 matches = "0.1.8"
 time = "0.1.42"
 
-[dev-dependencies.fail]
-version = "0.3"
-features = ["failpoints"]
-
 [profile.release]
 opt-level = 3
 debug = false
@@ -89,6 +87,10 @@ members = ["query-grammar"]
 [badges]
 travis-ci = { repository = "tantivy-search/tantivy" }
 
+[dev-dependencies.fail]
+version = "0.3"
+features = ["failpoints"]
+
 # Following the "fail" crate best practises, we isolate
 # tests that define specific behavior in fail check points
 # in a different binary.

examples/faceted_search.rs

@@ -13,100 +13,63 @@
 // ---
 // Importing tantivy...
 use tantivy::collector::FacetCollector;
-use tantivy::query::{AllQuery, TermQuery};
+use tantivy::query::AllQuery;
 use tantivy::schema::*;
 use tantivy::{doc, Index};
+use tempfile::TempDir;
 
 fn main() -> tantivy::Result<()> {
-    // Let's create a temporary directory for the sake of this example
+    // Let's create a temporary directory for the
+    // sake of this example
+    let index_path = TempDir::new()?;
     let mut schema_builder = Schema::builder();
 
-    let name = schema_builder.add_text_field("felin_name", TEXT | STORED);
-    // this is our faceted field: its scientific classification
-    let classification = schema_builder.add_facet_field("classification");
+    schema_builder.add_text_field("name", TEXT | STORED);
+
+    // this is our faceted field
+    schema_builder.add_facet_field("tags");
 
     let schema = schema_builder.build();
-    let index = Index::create_in_ram(schema);
 
-    let mut index_writer = index.writer(30_000_000)?;
+    let index = Index::create_in_dir(&index_path, schema.clone())?;
+
+    let mut index_writer = index.writer(50_000_000)?;
+
+    let name = schema.get_field("name").unwrap();
+    let tags = schema.get_field("tags").unwrap();
 
     // For convenience, tantivy also comes with a macro to
     // reduce the boilerplate above.
     index_writer.add_document(doc!(
-        name => "Cat",
-        classification => Facet::from("/Felidae/Felinae/Felis")
+        name => "the ditch",
+        tags => Facet::from("/pools/north")
     ));
+
     index_writer.add_document(doc!(
-        name => "Canada lynx",
-        classification => Facet::from("/Felidae/Felinae/Lynx")
-    ));
-    index_writer.add_document(doc!(
-        name => "Cheetah",
-        classification => Facet::from("/Felidae/Felinae/Acinonyx")
-    ));
-    index_writer.add_document(doc!(
-        name => "Tiger",
-        classification => Facet::from("/Felidae/Pantherinae/Panthera")
-    ));
-    index_writer.add_document(doc!(
-        name => "Lion",
-        classification => Facet::from("/Felidae/Pantherinae/Panthera")
-    ));
-    index_writer.add_document(doc!(
-        name => "Jaguar",
-        classification => Facet::from("/Felidae/Pantherinae/Panthera")
-    ));
-    index_writer.add_document(doc!(
-        name => "Sunda clouded leopard",
-        classification => Facet::from("/Felidae/Pantherinae/Neofelis")
-    ));
-    index_writer.add_document(doc!(
-        name => "Fossa",
-        classification => Facet::from("/Eupleridae/Cryptoprocta")
+        name => "little stacey",
+        tags => Facet::from("/pools/south")
     ));
+
     index_writer.commit()?;
 
     let reader = index.reader()?;
+
     let searcher = reader.searcher();
-    {
-        let mut facet_collector = FacetCollector::for_field(classification);
-        facet_collector.add_facet("/Felidae");
-        let facet_counts = searcher.search(&AllQuery, &facet_collector)?;
-        // This lists all of the facet counts, right below "/Felidae".
-        let facets: Vec<(&Facet, u64)> = facet_counts.get("/Felidae").collect();
-        assert_eq!(
-            facets,
-            vec![
-                (&Facet::from("/Felidae/Felinae"), 3),
-                (&Facet::from("/Felidae/Pantherinae"), 4),
-            ]
-        );
-    }
 
-    // Facets are also searchable.
-    //
-    // For instance a common UI pattern is to allow the user someone to click on a facet link
-    // (e.g: `Pantherinae`) to drill down and filter the current result set with this subfacet.
-    //
-    // The search would then look as follows.
+    let mut facet_collector = FacetCollector::for_field(tags);
+    facet_collector.add_facet("/pools");
 
-    // Check the reference doc for different ways to create a `Facet` object.
-    {
-        let facet = Facet::from_text("/Felidae/Pantherinae");
-        let facet_term = Term::from_facet(classification, &facet);
-        let facet_term_query = TermQuery::new(facet_term, IndexRecordOption::Basic);
-        let mut facet_collector = FacetCollector::for_field(classification);
-        facet_collector.add_facet("/Felidae/Pantherinae");
-        let facet_counts = searcher.search(&facet_term_query, &facet_collector)?;
-        let facets: Vec<(&Facet, u64)> = facet_counts.get("/Felidae/Pantherinae").collect();
-        assert_eq!(
-            facets,
-            vec![
-                (&Facet::from("/Felidae/Pantherinae/Neofelis"), 1),
-                (&Facet::from("/Felidae/Pantherinae/Panthera"), 3),
-            ]
-        );
-    }
+    let facet_counts = searcher.search(&AllQuery, &facet_collector).unwrap();
+
+    // This lists all of the facet counts
+    let facets: Vec<(&Facet, u64)> = facet_counts.get("/pools").collect();
+    assert_eq!(
+        facets,
+        vec![
+            (&Facet::from("/pools/north"), 1),
+            (&Facet::from("/pools/south"), 1),
+        ]
+    );
 
     Ok(())
 }

examples/pre_tokenized_text.rs

@@ -1,140 +0,0 @@
-// # Pre-tokenized text example
-//
-// This example shows how to use pre-tokenized text. Sometimes yout might
-// want to index and search through text which is already split into
-// tokens by some external tool.
-//
-// In this example we will:
-// - use tantivy tokenizer to create tokens and load them directly into tantivy,
-// - import tokenized text straight from json,
-// - perform a search on documents with pre-tokenized text
-
-use tantivy::tokenizer::{PreTokenizedString, SimpleTokenizer, Token, TokenStream, Tokenizer};
-
-use tantivy::collector::{Count, TopDocs};
-use tantivy::query::TermQuery;
-use tantivy::schema::*;
-use tantivy::{doc, Index, ReloadPolicy};
-use tempfile::TempDir;
-
-fn pre_tokenize_text(text: &str) -> Vec<Token> {
-    let mut token_stream = SimpleTokenizer.token_stream(text);
-    let mut tokens = vec![];
-    while token_stream.advance() {
-        tokens.push(token_stream.token().clone());
-    }
-    tokens
-}
-
-fn main() -> tantivy::Result<()> {
-    let index_path = TempDir::new()?;
-
-    let mut schema_builder = Schema::builder();
-
-    schema_builder.add_text_field("title", TEXT | STORED);
-    schema_builder.add_text_field("body", TEXT);
-
-    let schema = schema_builder.build();
-
-    let index = Index::create_in_dir(&index_path, schema.clone())?;
-
-    let mut index_writer = index.writer(50_000_000)?;
-
-    // We can create a document manually, by setting the fields
-    // one by one in a Document object.
-    let title = schema.get_field("title").unwrap();
-    let body = schema.get_field("body").unwrap();
-
-    let title_text = "The Old Man and the Sea";
-    let body_text = "He was an old man who fished alone in a skiff in the Gulf Stream";
-
-    // Content of our first document
-    // We create `PreTokenizedString` which contains original text and vector of tokens
-    let title_tok = PreTokenizedString {
-        text: String::from(title_text),
-        tokens: pre_tokenize_text(title_text),
-    };
-
-    println!(
-        "Original text: \"{}\" and tokens: {:?}",
-        title_tok.text, title_tok.tokens
-    );
-
-    let body_tok = PreTokenizedString {
-        text: String::from(body_text),
-        tokens: pre_tokenize_text(body_text),
-    };
-
-    // Now lets create a document and add our `PreTokenizedString`
-    let old_man_doc = doc!(title => title_tok, body => body_tok);
-
-    // ... now let's just add it to the IndexWriter
-    index_writer.add_document(old_man_doc);
-
-    // Pretokenized text can also be fed as JSON
-    let short_man_json = r#"{
-        "title":[{
-            "text":"The Old Man",
-            "tokens":[
-                {"offset_from":0,"offset_to":3,"position":0,"text":"The","position_length":1},
-                {"offset_from":4,"offset_to":7,"position":1,"text":"Old","position_length":1},
-                {"offset_from":8,"offset_to":11,"position":2,"text":"Man","position_length":1}
-            ]
-        }]
-    }"#;
-
-    let short_man_doc = schema.parse_document(&short_man_json)?;
-
-    index_writer.add_document(short_man_doc);
-
-    // Let's commit changes
-    index_writer.commit()?;
-
-    // ... and now is the time to query our index
-
-    let reader = index
-        .reader_builder()
-        .reload_policy(ReloadPolicy::OnCommit)
-        .try_into()?;
-
-    let searcher = reader.searcher();
-
-    // We want to get documents with token "Man", we will use TermQuery to do it
-    // Using PreTokenizedString means the tokens are stored as is avoiding stemming
-    // and lowercasing, which preserves full words in their original form
-    let query = TermQuery::new(
-        Term::from_field_text(title, "Man"),
-        IndexRecordOption::Basic,
-    );
-
-    let (top_docs, count) = searcher
-        .search(&query, &(TopDocs::with_limit(2), Count))
-        .unwrap();
-
-    assert_eq!(count, 2);
-
-    // Now let's print out the results.
-    // Note that the tokens are not stored along with the original text
-    // in the document store
-    for (_score, doc_address) in top_docs {
-        let retrieved_doc = searcher.doc(doc_address)?;
-        println!("Document: {}", schema.to_json(&retrieved_doc));
-    }
-
-    // In contrary to the previous query, when we search for the "man" term we
-    // should get no results, as it's not one of the indexed tokens. SimpleTokenizer
-    // only splits text on whitespace / punctuation.
-
-    let query = TermQuery::new(
-        Term::from_field_text(title, "man"),
-        IndexRecordOption::Basic,
-    );
-
-    let (_top_docs, count) = searcher
-        .search(&query, &(TopDocs::with_limit(2), Count))
-        .unwrap();
-
-    assert_eq!(count, 0);
-
-    Ok(())
-}

query-grammar/README.md

@@ -1,3 +0,0 @@
-# Tantivy Query Grammar
-
-This crate is used by tantivy to parse queries.

src/collector/count_collector.rs

@@ -13,29 +13,44 @@ use crate::SegmentReader;
 /// use tantivy::collector::Count;
 /// use tantivy::query::QueryParser;
 /// use tantivy::schema::{Schema, TEXT};
-/// use tantivy::{doc, Index};
+/// use tantivy::{doc, Index, Result};
 ///
-/// let mut schema_builder = Schema::builder();
-/// let title = schema_builder.add_text_field("title", TEXT);
-/// let schema = schema_builder.build();
-/// let index = Index::create_in_ram(schema);
+/// # fn main() { example().unwrap(); }
+/// fn example() -> Result<()> {
+///     let mut schema_builder = Schema::builder();
+///     let title = schema_builder.add_text_field("title", TEXT);
+///     let schema = schema_builder.build();
+///     let index = Index::create_in_ram(schema);
+///     {
+///         let mut index_writer = index.writer(3_000_000)?;
+///         index_writer.add_document(doc!(
+///             title => "The Name of the Wind",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of Muadib",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "A Dairy Cow",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of a Young Girl",
+///         ));
+///         index_writer.commit().unwrap();
+///     }
 ///
-/// let mut index_writer = index.writer(3_000_000).unwrap();
-/// index_writer.add_document(doc!(title => "The Name of the Wind"));
-/// index_writer.add_document(doc!(title => "The Diary of Muadib"));
-/// index_writer.add_document(doc!(title => "A Dairy Cow"));
-/// index_writer.add_document(doc!(title => "The Diary of a Young Girl"));
-/// assert!(index_writer.commit().is_ok());
+///     let reader = index.reader()?;
+///     let searcher = reader.searcher();
 ///
-/// let reader = index.reader().unwrap();
-/// let searcher = reader.searcher();
+///     {
+///         let query_parser = QueryParser::for_index(&index, vec![title]);
+///         let query = query_parser.parse_query("diary")?;
+///         let count = searcher.search(&query, &Count).unwrap();
 ///
-/// // Here comes the important part
-/// let query_parser = QueryParser::for_index(&index, vec![title]);
-/// let query = query_parser.parse_query("diary").unwrap();
-/// let count = searcher.search(&query, &Count).unwrap();
+///         assert_eq!(count, 2);
+///     }
 ///
-/// assert_eq!(count, 2);
+///     Ok(())
+/// }
 /// ```
 pub struct Count;
 

src/collector/facet_collector.rs

@@ -86,6 +86,7 @@ fn facet_depth(facet_bytes: &[u8]) -> usize {
 /// use tantivy::schema::{Facet, Schema, TEXT};
 /// use tantivy::{doc, Index, Result};
 ///
+/// # fn main() { example().unwrap(); }
 /// fn example() -> Result<()> {
 ///     let mut schema_builder = Schema::builder();
 ///
@@ -126,7 +127,7 @@ fn facet_depth(facet_bytes: &[u8]) -> usize {
 ///     let searcher = reader.searcher();
 ///
 ///     {
-///         let mut facet_collector = FacetCollector::for_field(facet);
+///			let mut facet_collector = FacetCollector::for_field(facet);
 ///         facet_collector.add_facet("/lang");
 ///         facet_collector.add_facet("/category");
 ///         let facet_counts = searcher.search(&AllQuery, &facet_collector)?;
@@ -142,7 +143,7 @@ fn facet_depth(facet_bytes: &[u8]) -> usize {
 ///     }
 ///
 ///     {
-///         let mut facet_collector = FacetCollector::for_field(facet);
+///			let mut facet_collector = FacetCollector::for_field(facet);
 ///         facet_collector.add_facet("/category/fiction");
 ///         let facet_counts = searcher.search(&AllQuery, &facet_collector)?;
 ///
@@ -157,8 +158,8 @@ fn facet_depth(facet_bytes: &[u8]) -> usize {
 ///         ]);
 ///     }
 ///
-///     {
-///         let mut facet_collector = FacetCollector::for_field(facet);
+///    {
+///			let mut facet_collector = FacetCollector::for_field(facet);
 ///         facet_collector.add_facet("/category/fiction");
 ///         let facet_counts = searcher.search(&AllQuery, &facet_collector)?;
 ///
@@ -171,7 +172,6 @@ fn facet_depth(facet_bytes: &[u8]) -> usize {
 ///
 ///     Ok(())
 /// }
-/// # assert!(example().is_ok());
 /// ```
 pub struct FacetCollector {
     field: Field,
@@ -452,11 +452,9 @@ impl FacetCounts {
 #[cfg(test)]
 mod tests {
     use super::{FacetCollector, FacetCounts};
-    use crate::collector::Count;
     use crate::core::Index;
-    use crate::query::{AllQuery, QueryParser, TermQuery};
-    use crate::schema::{Document, Facet, Field, IndexRecordOption, Schema};
-    use crate::Term;
+    use crate::query::AllQuery;
+    use crate::schema::{Document, Facet, Field, Schema};
     use rand::distributions::Uniform;
     use rand::prelude::SliceRandom;
     use rand::{thread_rng, Rng};
@@ -546,56 +544,6 @@ mod tests {
         assert_eq!(facets[0].1, 1);
     }
 
-    #[test]
-    fn test_doc_search_by_facet() {
-        let mut schema_builder = Schema::builder();
-        let facet_field = schema_builder.add_facet_field("facet");
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/A/A"),
-        ));
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/A/B"),
-        ));
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/A/C/A"),
-        ));
-        index_writer.add_document(doc!(
-            facet_field => Facet::from_text(&"/D/C/A"),
-        ));
-        index_writer.commit().unwrap();
-        let reader = index.reader().unwrap();
-        let searcher = reader.searcher();
-        assert_eq!(searcher.num_docs(), 4);
-
-        let count_facet = |facet_str: &str| {
-            let term = Term::from_facet(facet_field, &Facet::from_text(facet_str));
-            searcher
-                .search(&TermQuery::new(term, IndexRecordOption::Basic), &Count)
-                .unwrap()
-        };
-
-        assert_eq!(count_facet("/"), 4);
-        assert_eq!(count_facet("/A"), 3);
-        assert_eq!(count_facet("/A/B"), 1);
-        assert_eq!(count_facet("/A/C"), 1);
-        assert_eq!(count_facet("/A/C/A"), 1);
-        assert_eq!(count_facet("/C/A"), 0);
-        {
-            let query_parser = QueryParser::for_index(&index, vec![]);
-            {
-                let query = query_parser.parse_query("facet:/A/B").unwrap();
-                assert_eq!(1, searcher.search(&query, &Count).unwrap());
-            }
-            {
-                let query = query_parser.parse_query("facet:/A").unwrap();
-                assert_eq!(3, searcher.search(&query, &Count).unwrap());
-            }
-        }
-    }
-
     #[test]
     fn test_non_used_facet_collector() {
         let mut facet_collector = FacetCollector::for_field(Field::from_field_id(0));

src/collector/multi_collector.rs

@@ -108,35 +108,49 @@ impl<TFruit: Fruit> FruitHandle<TFruit> {
 /// use tantivy::collector::{Count, TopDocs, MultiCollector};
 /// use tantivy::query::QueryParser;
 /// use tantivy::schema::{Schema, TEXT};
-/// use tantivy::{doc, Index};
+/// use tantivy::{doc, Index, Result};
 ///
-/// let mut schema_builder = Schema::builder();
-/// let title = schema_builder.add_text_field("title", TEXT);
-/// let schema = schema_builder.build();
-/// let index = Index::create_in_ram(schema);
+/// # fn main() { example().unwrap(); }
+/// fn example() -> Result<()> {
+///     let mut schema_builder = Schema::builder();
+///     let title = schema_builder.add_text_field("title", TEXT);
+///     let schema = schema_builder.build();
+///     let index = Index::create_in_ram(schema);
+///     {
+///         let mut index_writer = index.writer(3_000_000)?;
+///         index_writer.add_document(doc!(
+///             title => "The Name of the Wind",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of Muadib",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "A Dairy Cow",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of a Young Girl",
+///         ));
+///         index_writer.commit().unwrap();
+///     }
 ///
-/// let mut index_writer = index.writer(3_000_000).unwrap();
-/// index_writer.add_document(doc!(title => "The Name of the Wind"));
-/// index_writer.add_document(doc!(title => "The Diary of Muadib"));
-/// index_writer.add_document(doc!(title => "A Dairy Cow"));
-/// index_writer.add_document(doc!(title => "The Diary of a Young Girl"));
-/// assert!(index_writer.commit().is_ok());
+///     let reader = index.reader()?;
+///     let searcher = reader.searcher();
 ///
-/// let reader = index.reader().unwrap();
-/// let searcher = reader.searcher();
+///     let mut collectors = MultiCollector::new();
+///     let top_docs_handle = collectors.add_collector(TopDocs::with_limit(2));
+///     let count_handle = collectors.add_collector(Count);
+///     let query_parser = QueryParser::for_index(&index, vec![title]);
+///     let query = query_parser.parse_query("diary")?;
+///     let mut multi_fruit = searcher.search(&query, &collectors)?;
 ///
-/// let mut collectors = MultiCollector::new();
-/// let top_docs_handle = collectors.add_collector(TopDocs::with_limit(2));
-/// let count_handle = collectors.add_collector(Count);
-/// let query_parser = QueryParser::for_index(&index, vec![title]);
-/// let query = query_parser.parse_query("diary").unwrap();
-/// let mut multi_fruit = searcher.search(&query, &collectors).unwrap();
+///     let count = count_handle.extract(&mut multi_fruit);
+///     let top_docs = top_docs_handle.extract(&mut multi_fruit);
 ///
-/// let count = count_handle.extract(&mut multi_fruit);
-/// let top_docs = top_docs_handle.extract(&mut multi_fruit);
+///     # assert_eq!(count, 2);
+///     # assert_eq!(top_docs.len(), 2);
 ///
-/// assert_eq!(count, 2);
-/// assert_eq!(top_docs.len(), 2);
+///     Ok(())
+/// }
 /// ```
 #[allow(clippy::type_complexity)]
 #[derive(Default)]

src/collector/top_collector.rs

@@ -12,9 +12,6 @@ use std::collections::BinaryHeap;
 /// It has a custom implementation of `PartialOrd` that reverses the order. This is because the
 /// default Rust heap is a max heap, whereas a min heap is needed.
 ///
-/// Additionally, it guarantees stable sorting: in case of a tie on the feature, the document
-/// address is used.
-///
 /// WARNING: equality is not what you would expect here.
 /// Two elements are equal if their feature is equal, and regardless of whether `doc`
 /// is equal. This should be perfectly fine for this usage, but let's make sure this
@@ -24,37 +21,29 @@ struct ComparableDoc<T, D> {
     doc: D,
 }
 
-impl<T: PartialOrd, D: PartialOrd> PartialOrd for ComparableDoc<T, D> {
+impl<T: PartialOrd, D> PartialOrd for ComparableDoc<T, D> {
     fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
         Some(self.cmp(other))
     }
 }
 
-impl<T: PartialOrd, D: PartialOrd> Ord for ComparableDoc<T, D> {
+impl<T: PartialOrd, D> Ord for ComparableDoc<T, D> {
     #[inline]
     fn cmp(&self, other: &Self) -> Ordering {
-        // Reversed to make BinaryHeap work as a min-heap
-        let by_feature = other
+        other
             .feature
             .partial_cmp(&self.feature)
-            .unwrap_or(Ordering::Equal);
-
-        let lazy_by_doc_address = || self.doc.partial_cmp(&other.doc).unwrap_or(Ordering::Equal);
-
-        // In case of a tie on the feature, we sort by ascending
-        // `DocAddress` in order to ensure a stable sorting of the
-        // documents.
-        by_feature.then_with(lazy_by_doc_address)
+            .unwrap_or_else(|| Ordering::Equal)
     }
 }
 
-impl<T: PartialOrd, D: PartialOrd> PartialEq for ComparableDoc<T, D> {
+impl<T: PartialOrd, D> PartialEq for ComparableDoc<T, D> {
     fn eq(&self, other: &Self) -> bool {
         self.cmp(other) == Ordering::Equal
     }
 }
 
-impl<T: PartialOrd, D: PartialOrd> Eq for ComparableDoc<T, D> {}
+impl<T: PartialOrd, D> Eq for ComparableDoc<T, D> {}
 
 pub(crate) struct TopCollector<T> {
     limit: usize,
@@ -225,94 +214,4 @@ mod tests {
             ]
         );
     }
-
-    #[test]
-    fn test_top_segment_collector_stable_ordering_for_equal_feature() {
-        // given that the documents are collected in ascending doc id order,
-        // when harvesting we have to guarantee stable sorting in case of a tie
-        // on the score
-        let doc_ids_collection = [4, 5, 6];
-        let score = 3.14;
-
-        let mut top_collector_limit_2 = TopSegmentCollector::new(0, 2);
-        for id in &doc_ids_collection {
-            top_collector_limit_2.collect(*id, score);
-        }
-
-        let mut top_collector_limit_3 = TopSegmentCollector::new(0, 3);
-        for id in &doc_ids_collection {
-            top_collector_limit_3.collect(*id, score);
-        }
-
-        assert_eq!(
-            top_collector_limit_2.harvest(),
-            top_collector_limit_3.harvest()[..2].to_vec(),
-        );
-    }
-}
-
-#[cfg(all(test, feature = "unstable"))]
-mod bench {
-    use super::TopSegmentCollector;
-    use test::Bencher;
-
-    #[bench]
-    fn bench_top_segment_collector_collect_not_at_capacity(b: &mut Bencher) {
-        let mut top_collector = TopSegmentCollector::new(0, 400);
-
-        b.iter(|| {
-            for i in 0..100 {
-                top_collector.collect(i, 0.8);
-            }
-        });
-    }
-
-    #[bench]
-    fn bench_top_segment_collector_collect_at_capacity(b: &mut Bencher) {
-        let mut top_collector = TopSegmentCollector::new(0, 100);
-
-        for i in 0..100 {
-            top_collector.collect(i, 0.8);
-        }
-
-        b.iter(|| {
-            for i in 0..100 {
-                top_collector.collect(i, 0.8);
-            }
-        });
-    }
-
-    #[bench]
-    fn bench_top_segment_collector_collect_and_harvest_many_ties(b: &mut Bencher) {
-        b.iter(|| {
-            let mut top_collector = TopSegmentCollector::new(0, 100);
-
-            for i in 0..100 {
-                top_collector.collect(i, 0.8);
-            }
-
-            // it would be nice to be able to do the setup N times but still
-            // measure only harvest(). We can't since harvest() consumes
-            // the top_collector.
-            top_collector.harvest()
-        });
-    }
-
-    #[bench]
-    fn bench_top_segment_collector_collect_and_harvest_no_tie(b: &mut Bencher) {
-        b.iter(|| {
-            let mut top_collector = TopSegmentCollector::new(0, 100);
-            let mut score = 1.0;
-
-            for i in 0..100 {
-                score += 1.0;
-                top_collector.collect(i, score);
-            }
-
-            // it would be nice to be able to do the setup N times but still
-            // measure only harvest(). We can't since harvest() consumes
-            // the top_collector.
-            top_collector.harvest()
-        });
-    }
 }

src/collector/top_score_collector.rs

@@ -15,43 +15,54 @@ use crate::SegmentLocalId;
 use crate::SegmentReader;
 use std::fmt;
 
-/// The `TopDocs` collector keeps track of the top `K` documents
+/// The Top Score Collector keeps track of the K documents
 /// sorted by their score.
 ///
 /// The implementation is based on a `BinaryHeap`.
 /// The theorical complexity for collecting the top `K` out of `n` documents
 /// is `O(n log K)`.
 ///
-/// This collector guarantees a stable sorting in case of a tie on the
-/// document score. As such, it is suitable to implement pagination.
-///
 /// ```rust
 /// use tantivy::collector::TopDocs;
 /// use tantivy::query::QueryParser;
 /// use tantivy::schema::{Schema, TEXT};
-/// use tantivy::{doc, DocAddress, Index};
+/// use tantivy::{doc, DocAddress, Index, Result};
 ///
-/// let mut schema_builder = Schema::builder();
-/// let title = schema_builder.add_text_field("title", TEXT);
-/// let schema = schema_builder.build();
-/// let index = Index::create_in_ram(schema);
+/// # fn main() { example().unwrap(); }
+/// fn example() -> Result<()> {
+///     let mut schema_builder = Schema::builder();
+///     let title = schema_builder.add_text_field("title", TEXT);
+///     let schema = schema_builder.build();
+///     let index = Index::create_in_ram(schema);
+///     {
+///         let mut index_writer = index.writer_with_num_threads(1, 3_000_000)?;
+///         index_writer.add_document(doc!(
+///             title => "The Name of the Wind",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of Muadib",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "A Dairy Cow",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of a Young Girl",
+///         ));
+///         index_writer.commit().unwrap();
+///     }
 ///
-/// let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-/// index_writer.add_document(doc!(title => "The Name of the Wind"));
-/// index_writer.add_document(doc!(title => "The Diary of Muadib"));
-/// index_writer.add_document(doc!(title => "A Dairy Cow"));
-/// index_writer.add_document(doc!(title => "The Diary of a Young Girl"));
-/// assert!(index_writer.commit().is_ok());
+///     let reader = index.reader()?;
+///     let searcher = reader.searcher();
 ///
-/// let reader = index.reader().unwrap();
-/// let searcher = reader.searcher();
+///     let query_parser = QueryParser::for_index(&index, vec![title]);
+///     let query = query_parser.parse_query("diary")?;
+///     let top_docs = searcher.search(&query, &TopDocs::with_limit(2))?;
 ///
-/// let query_parser = QueryParser::for_index(&index, vec![title]);
-/// let query = query_parser.parse_query("diary").unwrap();
-/// let top_docs = searcher.search(&query, &TopDocs::with_limit(2)).unwrap();
+///     assert_eq!(&top_docs[0], &(0.7261542, DocAddress(0, 1)));
+///     assert_eq!(&top_docs[1], &(0.6099695, DocAddress(0, 3)));
 ///
-/// assert_eq!(&top_docs[0], &(0.7261542, DocAddress(0, 1)));
-/// assert_eq!(&top_docs[1], &(0.6099695, DocAddress(0, 3)));
+///     Ok(())
+/// }
 /// ```
 pub struct TopDocs(TopCollector<Score>);
 
@@ -88,12 +99,15 @@ impl TopDocs {
     /// #  
     /// #   let index = Index::create_in_ram(schema);
     /// #   let mut index_writer = index.writer_with_num_threads(1, 3_000_000)?;
-    /// #   index_writer.add_document(doc!(title => "The Name of the Wind", rating => 92u64));
+    /// #   index_writer.add_document(doc!(
+    /// #       title => "The Name of the Wind",
+    /// #       rating => 92u64,
+    /// #   ));
     /// #   index_writer.add_document(doc!(title => "The Diary of Muadib", rating => 97u64));
     /// #   index_writer.add_document(doc!(title => "A Dairy Cow", rating => 63u64));
     /// #   index_writer.add_document(doc!(title => "The Diary of a Young Girl", rating => 80u64));
-    /// #   assert!(index_writer.commit().is_ok());
-    /// #   let reader = index.reader().unwrap();
+    /// #   index_writer.commit()?;
+    /// #   let reader = index.reader()?;
     /// #   let query = QueryParser::for_index(&index, vec![title]).parse_query("diary")?;
     /// #   let top_docs = docs_sorted_by_rating(&reader.searcher(), &query, rating)?;
     /// #   assert_eq!(top_docs,
@@ -185,33 +199,27 @@ impl TopDocs {
     /// use tantivy::collector::TopDocs;
     /// use tantivy::schema::Field;
     ///
-    /// fn create_schema() -> Schema {
-    ///    let mut schema_builder = Schema::builder();
-    ///    schema_builder.add_text_field("product_name", TEXT);
-    ///    schema_builder.add_u64_field("popularity", FAST);
-    ///    schema_builder.build()
-    /// }
-    ///
-    /// fn create_index() -> tantivy::Result<Index> {
-    ///   let schema = create_schema();
-    ///   let index = Index::create_in_ram(schema);
-    ///   let mut index_writer = index.writer_with_num_threads(1, 3_000_000)?;
-    ///   let product_name = index.schema().get_field("product_name").unwrap();
-    ///   let popularity: Field = index.schema().get_field("popularity").unwrap();
-    ///   index_writer.add_document(doc!(product_name => "The Diary of Muadib", popularity => 1u64));
-    ///   index_writer.add_document(doc!(product_name => "A Dairy Cow", popularity => 10u64));
-    ///   index_writer.add_document(doc!(product_name => "The Diary of a Young Girl", popularity => 15u64));
-    ///   index_writer.commit()?;
-    ///   Ok(index)
-    /// }
-    ///
-    /// let index = create_index().unwrap();
-    /// let product_name = index.schema().get_field("product_name").unwrap();
+    /// # fn create_schema() -> Schema {
+    /// #    let mut schema_builder = Schema::builder();
+    /// #    schema_builder.add_text_field("product_name", TEXT);
+    /// #    schema_builder.add_u64_field("popularity", FAST);
+    /// #    schema_builder.build()
+    /// # }
+    /// #
+    /// # fn main() -> tantivy::Result<()> {
+    /// #   let schema = create_schema();
+    /// #   let index = Index::create_in_ram(schema);
+    /// #   let mut index_writer = index.writer_with_num_threads(1, 3_000_000)?;
+    /// #   let product_name = index.schema().get_field("product_name").unwrap();
+    /// #   
     /// let popularity: Field = index.schema().get_field("popularity").unwrap();
-    ///
-    /// let user_query_str = "diary";
-    /// let query_parser = QueryParser::for_index(&index, vec![product_name]);
-    /// let query = query_parser.parse_query(user_query_str).unwrap();
+    /// #   index_writer.add_document(doc!(product_name => "The Diary of Muadib", popularity => 1u64));
+    /// #   index_writer.add_document(doc!(product_name => "A Dairy Cow", popularity => 10u64));
+    /// #   index_writer.add_document(doc!(product_name => "The Diary of a Young Girl", popularity => 15u64));
+    /// #   index_writer.commit()?;
+    /// // ...
+    /// # let user_query = "diary";
+    /// # let query = QueryParser::for_index(&index, vec![product_name]).parse_query(user_query)?;
     ///
     /// // This is where we build our collector with our custom score.
     /// let top_docs_by_custom_score = TopDocs
@@ -238,12 +246,15 @@ impl TopDocs {
     ///                 popularity_boost_score * original_score
     ///             }
     ///           });
-    /// let reader = index.reader().unwrap();
-    /// let searcher = reader.searcher();
+    /// # let reader = index.reader()?;
+    /// # let searcher = reader.searcher();
     /// // ... and here are our documents. Note this is a simple vec.
     /// // The `Score` in the pair is our tweaked score.
     /// let resulting_docs: Vec<(Score, DocAddress)> =
-    ///      searcher.search(&query, &top_docs_by_custom_score).unwrap();
+    ///      searcher.search(&*query, &top_docs_by_custom_score)?;
+    ///
+    /// # Ok(())
+    /// # }
     /// ```
     ///
     /// # See also
@@ -417,13 +428,12 @@ impl SegmentCollector for TopScoreSegmentCollector {
 mod tests {
     use super::TopDocs;
     use crate::collector::Collector;
-    use crate::query::{AllQuery, Query, QueryParser};
+    use crate::query::{Query, QueryParser};
     use crate::schema::{Field, Schema, FAST, STORED, TEXT};
     use crate::DocAddress;
     use crate::Index;
     use crate::IndexWriter;
     use crate::Score;
-    use itertools::Itertools;
 
     fn make_index() -> Index {
         let mut schema_builder = Schema::builder();
@@ -484,29 +494,6 @@ mod tests {
         );
     }
 
-    #[test]
-    fn test_top_collector_stable_sorting() {
-        let index = make_index();
-
-        // using AllQuery to get a constant score
-        let searcher = index.reader().unwrap().searcher();
-
-        let page_1 = searcher.search(&AllQuery, &TopDocs::with_limit(2)).unwrap();
-
-        let page_2 = searcher.search(&AllQuery, &TopDocs::with_limit(3)).unwrap();
-
-        // precondition for the test to be meaningful: we did get documents
-        // with the same score
-        assert!(page_1.iter().map(|result| result.0).all_equal());
-        assert!(page_2.iter().map(|result| result.0).all_equal());
-
-        // sanity check since we're relying on make_index()
-        assert_eq!(page_1.len(), 2);
-        assert_eq!(page_2.len(), 3);
-
-        assert_eq!(page_1, &page_2[..page_1.len()]);
-    }
-
     #[test]
     #[should_panic]
     fn test_top_0() {

src/common/composite_file.rs

@@ -186,7 +186,7 @@ mod test {
     use super::{CompositeFile, CompositeWrite};
     use crate::common::BinarySerializable;
     use crate::common::VInt;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory};
+    use crate::directory::{Directory, RAMDirectory};
     use crate::schema::Field;
     use std::io::Write;
     use std::path::Path;

src/core/executor.rs

@@ -1,6 +1,6 @@
 use crate::Result;
 use crossbeam::channel;
-use rayon::{ThreadPool, ThreadPoolBuilder};
+use scoped_pool::{Pool, ThreadConfig};
 
 /// Search executor whether search request are single thread or multithread.
 ///
@@ -11,7 +11,7 @@ use rayon::{ThreadPool, ThreadPoolBuilder};
 /// used by the client. Second, we may stop using rayon in the future.
 pub enum Executor {
     SingleThread,
-    ThreadPool(ThreadPool),
+    ThreadPool(Pool),
 }
 
 impl Executor {
@@ -21,12 +21,10 @@ impl Executor {
     }
 
     // Creates an Executor that dispatches the tasks in a thread pool.
-    pub fn multi_thread(num_threads: usize, prefix: &'static str) -> Result<Executor> {
-        let pool = ThreadPoolBuilder::new()
-            .num_threads(num_threads)
-            .thread_name(move |num| format!("{}{}", prefix, num))
-            .build()?;
-        Ok(Executor::ThreadPool(pool))
+    pub fn multi_thread(num_threads: usize, prefix: &'static str) -> Executor {
+        let thread_config = ThreadConfig::new().prefix(prefix);
+        let pool = Pool::with_thread_config(num_threads, thread_config);
+        Executor::ThreadPool(pool)
     }
 
     // Perform a map in the thread pool.
@@ -50,9 +48,9 @@ impl Executor {
                 let num_fruits = args_with_indices.len();
                 let fruit_receiver = {
                     let (fruit_sender, fruit_receiver) = channel::unbounded();
-                    pool.scope(|scope| {
+                    pool.scoped(|scope| {
                         for arg_with_idx in args_with_indices {
-                            scope.spawn(|_| {
+                            scope.execute(|| {
                                 let (idx, arg) = arg_with_idx;
                                 let fruit = f(arg);
                                 if let Err(err) = fruit_sender.send((idx, fruit)) {
@@ -105,7 +103,6 @@ mod tests {
     #[should_panic] //< unfortunately the panic message is not propagated
     fn test_panic_propagates_multi_thread() {
         let _result: Vec<usize> = Executor::multi_thread(1, "search-test")
-            .unwrap()
             .map(
                 |_| {
                     panic!("panic should propagate");
@@ -129,7 +126,6 @@ mod tests {
     #[test]
     fn test_map_multithread() {
         let result: Vec<usize> = Executor::multi_thread(3, "search-test")
-            .unwrap()
             .map(|i| Ok(i * 2), 0..10)
             .unwrap();
         assert_eq!(result.len(), 10);

src/core/index.rs

@@ -73,16 +73,15 @@ impl Index {
 
     /// Replace the default single thread search executor pool
     /// by a thread pool with a given number of threads.
-    pub fn set_multithread_executor(&mut self, num_threads: usize) -> Result<()> {
-        self.executor = Arc::new(Executor::multi_thread(num_threads, "thrd-tantivy-search-")?);
-        Ok(())
+    pub fn set_multithread_executor(&mut self, num_threads: usize) {
+        self.executor = Arc::new(Executor::multi_thread(num_threads, "thrd-tantivy-search-"));
     }
 
     /// Replace the default single thread search executor pool
     /// by a thread pool with a given number of threads.
-    pub fn set_default_multithread_executor(&mut self) -> Result<()> {
+    pub fn set_default_multithread_executor(&mut self) {
         let default_num_threads = num_cpus::get();
-        self.set_multithread_executor(default_num_threads)
+        self.set_multithread_executor(default_num_threads);
     }
 
     /// Creates a new index using the `RAMDirectory`.
@@ -104,21 +103,23 @@ impl Index {
         if Index::exists(&mmap_directory) {
             return Err(TantivyError::IndexAlreadyExists);
         }
+
         Index::create(mmap_directory, schema)
     }
 
     /// Opens or creates a new index in the provided directory
     pub fn open_or_create<Dir: Directory>(dir: Dir, schema: Schema) -> Result<Index> {
-        if !Index::exists(&dir) {
-            return Index::create(dir, schema);
-        }
-        let index = Index::open(dir)?;
-        if index.schema() == schema {
-            Ok(index)
+        if Index::exists(&dir) {
+            let index = Index::open(dir)?;
+            if index.schema() == schema {
+                Ok(index)
+            } else {
+                Err(TantivyError::SchemaError(
+                    "An index exists but the schema does not match.".to_string(),
+                ))
+            }
         } else {
-            Err(TantivyError::SchemaError(
-                "An index exists but the schema does not match.".to_string(),
-            ))
+            Index::create(dir, schema)
         }
     }
 
@@ -338,7 +339,7 @@ impl Index {
 
     /// Creates a new segment.
     pub fn new_segment(&self) -> Segment {
-        let mut segment_meta = self
+        let segment_meta = self
             .inventory
             .new_segment_meta(SegmentId::generate_random(), 0);
         self.segment(segment_meta)
@@ -386,9 +387,12 @@ mod tests {
     use crate::directory::RAMDirectory;
     use crate::schema::Field;
     use crate::schema::{Schema, INDEXED, TEXT};
+    use crate::Index;
     use crate::IndexReader;
+    use crate::IndexWriter;
     use crate::ReloadPolicy;
-    use crate::{Directory, Index};
+    use std::thread;
+    use std::time::Duration;
 
     #[test]
     fn test_indexer_for_field() {
@@ -466,14 +470,14 @@ mod tests {
             .try_into()
             .unwrap();
         assert_eq!(reader.searcher().num_docs(), 0);
-        test_index_on_commit_reload_policy_aux(field, &index, &reader);
+        let mut writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
+        test_index_on_commit_reload_policy_aux(field, &mut writer, &reader);
     }
 
     #[cfg(feature = "mmap")]
     mod mmap_specific {
 
         use super::*;
-        use crate::Directory;
         use std::path::PathBuf;
         use tempfile::TempDir;
 
@@ -484,20 +488,22 @@ mod tests {
             let tempdir = TempDir::new().unwrap();
             let tempdir_path = PathBuf::from(tempdir.path());
             let index = Index::create_in_dir(&tempdir_path, schema).unwrap();
+            let mut writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
+            writer.commit().unwrap();
             let reader = index
                 .reader_builder()
                 .reload_policy(ReloadPolicy::OnCommit)
                 .try_into()
                 .unwrap();
             assert_eq!(reader.searcher().num_docs(), 0);
-            test_index_on_commit_reload_policy_aux(field, &index, &reader);
+            test_index_on_commit_reload_policy_aux(field, &mut writer, &reader);
         }
 
         #[test]
         fn test_index_manual_policy_mmap() {
             let schema = throw_away_schema();
             let field = schema.get_field("num_likes").unwrap();
-            let mut index = Index::create_from_tempdir(schema).unwrap();
+            let index = Index::create_from_tempdir(schema).unwrap();
             let mut writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
             writer.commit().unwrap();
             let reader = index
@@ -507,12 +513,8 @@ mod tests {
                 .unwrap();
             assert_eq!(reader.searcher().num_docs(), 0);
             writer.add_document(doc!(field=>1u64));
-            let (sender, receiver) = crossbeam::channel::unbounded();
-            let _handle = index.directory_mut().watch(Box::new(move || {
-                let _ = sender.send(());
-            }));
             writer.commit().unwrap();
-            assert!(receiver.recv().is_ok());
+            thread::sleep(Duration::from_millis(500));
             assert_eq!(reader.searcher().num_docs(), 0);
             reader.reload().unwrap();
             assert_eq!(reader.searcher().num_docs(), 1);
@@ -532,26 +534,39 @@ mod tests {
                 .try_into()
                 .unwrap();
             assert_eq!(reader.searcher().num_docs(), 0);
-            test_index_on_commit_reload_policy_aux(field, &write_index, &reader);
+            let mut writer = write_index.writer_with_num_threads(1, 3_000_000).unwrap();
+            test_index_on_commit_reload_policy_aux(field, &mut writer, &reader);
         }
     }
 
-    fn test_index_on_commit_reload_policy_aux(field: Field, index: &Index, reader: &IndexReader) {
-        let mut reader_index = reader.index();
-        let (sender, receiver) = crossbeam::channel::unbounded();
-        let _watch_handle = reader_index.directory_mut().watch(Box::new(move || {
-            let _ = sender.send(());
-        }));
-        let mut writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
+    fn test_index_on_commit_reload_policy_aux(
+        field: Field,
+        writer: &mut IndexWriter,
+        reader: &IndexReader,
+    ) {
         assert_eq!(reader.searcher().num_docs(), 0);
         writer.add_document(doc!(field=>1u64));
         writer.commit().unwrap();
-        assert!(receiver.recv().is_ok());
-        assert_eq!(reader.searcher().num_docs(), 1);
+        let mut count = 0;
+        for _ in 0..100 {
+            count = reader.searcher().num_docs();
+            if count > 0 {
+                break;
+            }
+            thread::sleep(Duration::from_millis(100));
+        }
+        assert_eq!(count, 1);
         writer.add_document(doc!(field=>2u64));
         writer.commit().unwrap();
-        assert!(receiver.recv().is_ok());
-        assert_eq!(reader.searcher().num_docs(), 2);
+        let mut count = 0;
+        for _ in 0..10 {
+            count = reader.searcher().num_docs();
+            if count > 1 {
+                break;
+            }
+            thread::sleep(Duration::from_millis(100));
+        }
+        assert_eq!(count, 2);
     }
 
     // This test will not pass on windows, because windows
@@ -568,13 +583,9 @@ mod tests {
         for i in 0u64..8_000u64 {
             writer.add_document(doc!(field => i));
         }
-        let (sender, receiver) = crossbeam::channel::unbounded();
-        let _handle = directory.watch(Box::new(move || {
-            let _ = sender.send(());
-        }));
         writer.commit().unwrap();
         let mem_right_after_commit = directory.total_mem_usage();
-        assert!(receiver.recv().is_ok());
+        thread::sleep(Duration::from_millis(1_000));
         let reader = index
             .reader_builder()
             .reload_policy(ReloadPolicy::Manual)
@@ -588,11 +599,6 @@ mod tests {
         reader.reload().unwrap();
         let searcher = reader.searcher();
         assert_eq!(searcher.num_docs(), 8_000);
-        assert!(
-            mem_right_after_merge_finished < mem_right_after_commit,
-            "(mem after merge){} is expected < (mem before merge){}",
-            mem_right_after_merge_finished,
-            mem_right_after_commit
-        );
+        assert!(mem_right_after_merge_finished < mem_right_after_commit);
     }
 }

src/core/index_meta.rs

@@ -35,7 +35,6 @@ impl SegmentMetaInventory {
             segment_id,
             max_doc,
             deletes: None,
-            bundled: false,
         };
         SegmentMeta::from(self.inventory.track(inner))
     }
@@ -82,19 +81,6 @@ impl SegmentMeta {
         self.tracked.segment_id
     }
 
-    pub fn with_bundled(self) -> SegmentMeta {
-        SegmentMeta::from(self.tracked.map(|inner| InnerSegmentMeta {
-            segment_id: inner.segment_id,
-            max_doc: inner.max_doc,
-            deletes: inner.deletes.clone(),
-            bundled: true,
-        }))
-    }
-
-    pub fn is_bundled(&self) -> bool {
-        self.tracked.bundled
-    }
-
     /// Returns the number of deleted documents.
     pub fn num_deleted_docs(&self) -> u32 {
         self.tracked
@@ -121,12 +107,8 @@ impl SegmentMeta {
     /// It just joins the segment id with the extension
     /// associated to a segment component.
     pub fn relative_path(&self, component: SegmentComponent) -> PathBuf {
-        let suffix = self.suffix(component);
-        self.relative_path_from_suffix(&suffix)
-    }
-
-    fn suffix(&self, component: SegmentComponent) -> String {
-        match component {
+        let mut path = self.id().uuid_string();
+        path.push_str(&*match component {
             SegmentComponent::POSTINGS => ".idx".to_string(),
             SegmentComponent::POSITIONS => ".pos".to_string(),
             SegmentComponent::POSITIONSSKIP => ".posidx".to_string(),
@@ -135,17 +117,7 @@ impl SegmentMeta {
             SegmentComponent::FASTFIELDS => ".fast".to_string(),
             SegmentComponent::FIELDNORMS => ".fieldnorm".to_string(),
             SegmentComponent::DELETE => format!(".{}.del", self.delete_opstamp().unwrap_or(0)),
-        }
-    }
-
-    /// Returns the relative path of a component of our segment.
-    ///
-    /// It just joins the segment id with the extension
-    /// associated to a segment component.
-    pub fn relative_path_from_suffix(&self, suffix: &str) -> PathBuf {
-        let mut path = self.id().uuid_string();
-        path.push_str(".");
-        path.push_str(&suffix);
+        });
         PathBuf::from(path)
     }
 
@@ -178,22 +150,6 @@ impl SegmentMeta {
         self.num_deleted_docs() > 0
     }
 
-    /// Updates the max_doc value from the `SegmentMeta`.
-    ///
-    /// This method is only used when updating `max_doc` from 0
-    /// as we finalize a fresh new segment.
-    pub(crate) fn with_max_doc(self, max_doc: u32) -> SegmentMeta {
-        assert_eq!(self.tracked.max_doc, 0);
-        assert!(self.tracked.deletes.is_none());
-        let tracked = self.tracked.map(move |inner_meta| InnerSegmentMeta {
-            segment_id: inner_meta.segment_id,
-            max_doc,
-            deletes: None,
-            bundled: inner_meta.bundled,
-        });
-        SegmentMeta { tracked }
-    }
-
     #[doc(hidden)]
     pub fn with_delete_meta(self, num_deleted_docs: u32, opstamp: Opstamp) -> SegmentMeta {
         let delete_meta = DeleteMeta {
@@ -204,7 +160,6 @@ impl SegmentMeta {
             segment_id: inner_meta.segment_id,
             max_doc: inner_meta.max_doc,
             deletes: Some(delete_meta),
-            bundled: inner_meta.bundled,
         });
         SegmentMeta { tracked }
     }
@@ -215,7 +170,6 @@ struct InnerSegmentMeta {
     segment_id: SegmentId,
     max_doc: u32,
     deletes: Option<DeleteMeta>,
-    bundled: bool,
 }
 
 impl InnerSegmentMeta {
@@ -331,9 +285,6 @@ mod tests {
             payload: None,
         };
         let json = serde_json::ser::to_string(&index_metas).expect("serialization failed");
-        assert_eq!(
-            json,
-            r#"{"segments":[],"schema":[{"name":"text","type":"text","options":{"indexing":{"record":"position","tokenizer":"default"},"stored":false}}],"opstamp":0}"#
-        );
+        assert_eq!(json, r#"{"segments":[],"schema":[{"name":"text","type":"text","options":{"indexing":{"record":"position","tokenizer":"default"},"stored":false}}],"opstamp":0}"#);
     }
 }

src/core/segment.rs

@@ -4,12 +4,14 @@ use crate::core::SegmentId;
 use crate::core::SegmentMeta;
 use crate::directory::error::{OpenReadError, OpenWriteError};
 use crate::directory::Directory;
-use crate::directory::{ReadOnlyDirectory, ReadOnlySource, WritePtr};
+use crate::directory::{ReadOnlySource, WritePtr};
 use crate::indexer::segment_serializer::SegmentSerializer;
 use crate::schema::Schema;
 use crate::Opstamp;
+use crate::Result;
 use std::fmt;
 use std::path::PathBuf;
+use std::result;
 
 /// A segment is a piece of the index.
 #[derive(Clone)]
@@ -48,17 +50,6 @@ impl Segment {
         &self.meta
     }
 
-    /// Updates the max_doc value from the `SegmentMeta`.
-    ///
-    /// This method is only used when updating `max_doc` from 0
-    /// as we finalize a fresh new segment.
-    pub(crate) fn with_max_doc(self, max_doc: u32) -> Segment {
-        Segment {
-            index: self.index,
-            meta: self.meta.with_max_doc(max_doc),
-        }
-    }
-
     #[doc(hidden)]
     pub fn with_delete_meta(self, num_deleted_docs: u32, opstamp: Opstamp) -> Segment {
         Segment {
@@ -81,30 +72,23 @@ impl Segment {
     }
 
     /// Open one of the component file for a *regular* read.
-    pub fn open_read(&self, component: SegmentComponent) -> Result<ReadOnlySource, OpenReadError> {
+    pub fn open_read(
+        &self,
+        component: SegmentComponent,
+    ) -> result::Result<ReadOnlySource, OpenReadError> {
         let path = self.relative_path(component);
         let source = self.index.directory().open_read(&path)?;
         Ok(source)
     }
 
     /// Open one of the component file for *regular* write.
-    pub fn open_write(&mut self, component: SegmentComponent) -> Result<WritePtr, OpenWriteError> {
-        let path = self.relative_path(component);
-        self.index.directory_mut().open_write(&path)
-    }
-
-    pub fn open_bundle_writer(&mut self) -> Result<WritePtr, OpenWriteError> {
-        let path = self.meta.relative_path_from_suffix("bundle");
-        self.index.directory_mut().open_write(&path)
-    }
-
-    pub(crate) fn open_write_in_directory(
+    pub fn open_write(
         &mut self,
         component: SegmentComponent,
-        directory: &mut dyn Directory,
-    ) -> Result<WritePtr, OpenWriteError> {
+    ) -> result::Result<WritePtr, OpenWriteError> {
         let path = self.relative_path(component);
-        directory.open_write(&path)
+        let write = self.index.directory_mut().open_write(&path)?;
+        Ok(write)
     }
 }
 
@@ -114,5 +98,5 @@ pub trait SerializableSegment {
     ///
     /// # Returns
     /// The number of documents in the segment.
-    fn write(&self, serializer: SegmentSerializer) -> crate::Result<u32>;
+    fn write(&self, serializer: SegmentSerializer) -> Result<u32>;
 }

src/core/segment_id.rs

@@ -76,7 +76,7 @@ impl SegmentId {
 }
 
 /// Error type used when parsing a `SegmentId` from a string fails.
-pub struct SegmentIdParseError(uuid::Error);
+pub struct SegmentIdParseError(uuid::parser::ParseError);
 
 impl Error for SegmentIdParseError {}
 

src/directory/bundle_directory.rs

@@ -1,97 +0,0 @@
-use crate::directory::directory::ReadOnlyDirectory;
-use crate::directory::error::OpenReadError;
-use crate::directory::ReadOnlySource;
-use crate::error::DataCorruption;
-use std::collections::HashMap;
-use std::path::{Path, PathBuf};
-use std::sync::Arc;
-
-#[derive(Clone)]
-struct BundleDirectory {
-    source_map: Arc<HashMap<PathBuf, ReadOnlySource>>,
-}
-
-impl BundleDirectory {
-    pub fn from_source(source: ReadOnlySource) -> Result<BundleDirectory, DataCorruption> {
-        let mut index_offset_buf = [0u8; 8];
-        let (body_idx, footer_offset) = source.split_from_end(8);
-        index_offset_buf.copy_from_slice(footer_offset.as_slice());
-        let offset = u64::from_le_bytes(index_offset_buf);
-        let (body_source, idx_source) = body_idx.split(offset as usize);
-        let idx: HashMap<PathBuf, (u64, u64)> = serde_json::from_slice(idx_source.as_slice())
-            .map_err(|err| {
-                let msg = format!("Failed to read index from bundle. {:?}", err);
-                DataCorruption::comment_only(msg)
-            })?;
-        let source_map: HashMap<PathBuf, ReadOnlySource> = idx
-            .into_iter()
-            .map(|(path, (start, stop))| {
-                let source = body_source.slice(start as usize, stop as usize);
-                (path, source)
-            })
-            .collect();
-        Ok(BundleDirectory {
-            source_map: Arc::new(source_map),
-        })
-    }
-}
-
-impl ReadOnlyDirectory for BundleDirectory {
-    fn open_read(&self, path: &Path) -> Result<ReadOnlySource, OpenReadError> {
-        self.source_map
-            .get(path)
-            .cloned()
-            .ok_or_else(|| OpenReadError::FileDoesNotExist(path.to_path_buf()))
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        self.source_map.contains_key(path)
-    }
-
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
-        let source = self
-            .source_map
-            .get(path)
-            .ok_or_else(|| OpenReadError::FileDoesNotExist(path.to_path_buf()))?;
-        Ok(source.as_slice().to_vec())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::BundleDirectory;
-    use crate::directory::{RAMDirectory, ReadOnlyDirectory, TerminatingWrite};
-    use crate::Directory;
-    use std::io::Write;
-    use std::path::Path;
-
-    #[test]
-    fn test_bundle_directory() {
-        let mut ram_directory = RAMDirectory::default();
-        let test_path_atomic = Path::new("testpath_atomic");
-        let test_path_wrt = Path::new("testpath_wrt");
-        assert!(ram_directory
-            .atomic_write(test_path_atomic, b"titi")
-            .is_ok());
-        {
-            let mut test_wrt = ram_directory.open_write(test_path_wrt).unwrap();
-            assert!(test_wrt.write_all(b"toto").is_ok());
-            assert!(test_wrt.terminate().is_ok());
-        }
-        let mut dest_directory = RAMDirectory::default();
-        let bundle_path = Path::new("bundle");
-        let mut wrt = dest_directory.open_write(bundle_path).unwrap();
-        assert!(ram_directory.serialize_bundle(&mut wrt).is_ok());
-        assert!(wrt.terminate().is_ok());
-        let source = dest_directory.open_read(bundle_path).unwrap();
-        let bundle_directory = BundleDirectory::from_source(source).unwrap();
-        assert_eq!(
-            &bundle_directory.atomic_read(test_path_atomic).unwrap()[..],
-            b"titi"
-        );
-        assert_eq!(
-            &bundle_directory.open_read(test_path_wrt).unwrap()[..],
-            b"toto"
-        );
-    }
-}

src/directory/directory.rs

@@ -100,30 +100,6 @@ fn retry_policy(is_blocking: bool) -> RetryPolicy {
     }
 }
 
-pub trait ReadOnlyDirectory {
-    /// Opens a virtual file for read.
-    ///
-    /// Once a virtual file is open, its data may not
-    /// change.
-    ///
-    /// Specifically, subsequent writes or flushes should
-    /// have no effect on the returned `ReadOnlySource` object.
-    ///
-    /// You should only use this to read files create with [Directory::open_write].
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError>;
-
-    /// Returns true iff the file exists
-    fn exists(&self, path: &Path) -> bool;
-
-    /// Reads the full content file that has been written using
-    /// atomic_write.
-    ///
-    /// This should only be used for small files.
-    ///
-    /// You should only use this to read files create with [Directory::atomic_write].
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError>;
-}
-
 /// Write-once read many (WORM) abstraction for where
 /// tantivy's data should be stored.
 ///
@@ -134,9 +110,18 @@ pub trait ReadOnlyDirectory {
 /// - The [`RAMDirectory`](struct.RAMDirectory.html), which
 /// should be used mostly for tests.
 ///
-pub trait Directory:
-    DirectoryClone + ReadOnlyDirectory + fmt::Debug + Send + Sync + 'static
-{
+pub trait Directory: DirectoryClone + fmt::Debug + Send + Sync + 'static {
+    /// Opens a virtual file for read.
+    ///
+    /// Once a virtual file is open, its data may not
+    /// change.
+    ///
+    /// Specifically, subsequent writes or flushes should
+    /// have no effect on the returned `ReadOnlySource` object.
+    ///
+    /// You should only use this to read files create with [`open_write`]
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError>;
+
     /// Removes a file
     ///
     /// Removing a file will not affect an eventual
@@ -146,6 +131,9 @@ pub trait Directory:
     /// `DeleteError::DoesNotExist`.
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError>;
 
+    /// Returns true iff the file exists
+    fn exists(&self, path: &Path) -> bool;
+
     /// Opens a writer for the *virtual file* associated with
     /// a Path.
     ///
@@ -167,6 +155,14 @@ pub trait Directory:
     /// The file may not previously exist.
     fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError>;
 
+    /// Reads the full content file that has been written using
+    /// atomic_write.
+    ///
+    /// This should only be used for small files.
+    ///
+    /// You should only use this to read files create with [`atomic_write`]
+    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError>;
+
     /// Atomically replace the content of a file with data.
     ///
     /// This calls ensure that reads can never *observe*
@@ -201,7 +197,7 @@ pub trait Directory:
     /// Registers a callback that will be called whenever a change on the `meta.json`
     /// using the `atomic_write` API is detected.
     ///
-    /// The behavior when using `.watch()` on a file using [Directory::open_write] is, on the other
+    /// The behavior when using `.watch()` on a file using `.open_write(...)` is, on the other
     /// hand, undefined.
     ///
     /// The file will be watched for the lifetime of the returned `WatchHandle`. The caller is

src/directory/error.rs

@@ -1,4 +1,3 @@
-use crate::Version;
 use std::error::Error as StdError;
 use std::fmt;
 use std::io;
@@ -157,65 +156,6 @@ impl StdError for OpenWriteError {
     }
 }
 
-/// Type of index incompatibility between the library and the index found on disk
-/// Used to catch and provide a hint to solve this incompatibility issue
-pub enum Incompatibility {
-    /// This library cannot decompress the index found on disk
-    CompressionMismatch {
-        /// Compression algorithm used by the current version of tantivy
-        library_compression_format: String,
-        /// Compression algorithm that was used to serialise the index
-        index_compression_format: String,
-    },
-    /// The index format found on disk isn't supported by this version of the library
-    IndexMismatch {
-        /// Version used by the library
-        library_version: Version,
-        /// Version the index was built with
-        index_version: Version,
-    },
-}
-
-impl fmt::Debug for Incompatibility {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        match self {
-            Incompatibility::CompressionMismatch {
-                library_compression_format,
-                index_compression_format,
-            } => {
-                let err = format!(
-                    "Library was compiled with {:?} compression, index was compressed with {:?}",
-                    library_compression_format, index_compression_format
-                );
-                let advice = format!(
-                    "Change the feature flag to {:?} and rebuild the library",
-                    index_compression_format
-                );
-                write!(f, "{}. {}", err, advice)?;
-            }
-            Incompatibility::IndexMismatch {
-                library_version,
-                index_version,
-            } => {
-                let err = format!(
-                    "Library version: {}, index version: {}",
-                    library_version.index_format_version, index_version.index_format_version
-                );
-                // TODO make a more useful error message
-                // include the version range that supports this index_format_version
-                let advice = format!(
-                    "Change tantivy to a version compatible with index format {} (e.g. {}.{}.x) \
-                     and rebuild your project.",
-                    index_version.index_format_version, index_version.major, index_version.minor
-                );
-                write!(f, "{}. {}", err, advice)?;
-            }
-        }
-
-        Ok(())
-    }
-}
-
 /// Error that may occur when accessing a file read
 #[derive(Debug)]
 pub enum OpenReadError {
@@ -224,8 +164,6 @@ pub enum OpenReadError {
     /// Any kind of IO error that happens when
     /// interacting with the underlying IO device.
     IOError(IOError),
-    /// This library doesn't support the index version found on disk
-    IncompatibleIndex(Incompatibility),
 }
 
 impl From<IOError> for OpenReadError {
@@ -245,9 +183,19 @@ impl fmt::Display for OpenReadError {
                 "an io error occurred while opening a file for reading: '{}'",
                 err
             ),
-            OpenReadError::IncompatibleIndex(ref footer) => {
-                write!(f, "Incompatible index format: {:?}", footer)
-            }
+        }
+    }
+}
+
+impl StdError for OpenReadError {
+    fn description(&self) -> &str {
+        "error occurred while opening a file for reading"
+    }
+
+    fn cause(&self) -> Option<&dyn StdError> {
+        match *self {
+            OpenReadError::FileDoesNotExist(_) => None,
+            OpenReadError::IOError(ref err) => Some(err),
         }
     }
 }
@@ -268,12 +216,6 @@ impl From<IOError> for DeleteError {
     }
 }
 
-impl From<Incompatibility> for OpenReadError {
-    fn from(incompatibility: Incompatibility) -> Self {
-        OpenReadError::IncompatibleIndex(incompatibility)
-    }
-}
-
 impl fmt::Display for DeleteError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {

src/directory/footer.rs

@@ -1,175 +1,159 @@
-use crate::common::{BinarySerializable, CountingWriter, FixedSize, VInt};
-use crate::directory::error::Incompatibility;
 use crate::directory::read_only_source::ReadOnlySource;
 use crate::directory::{AntiCallToken, TerminatingWrite};
-use crate::Version;
-use byteorder::{ByteOrder, LittleEndian, WriteBytesExt};
+use byteorder::{ByteOrder, LittleEndian};
 use crc32fast::Hasher;
 use std::io;
 use std::io::Write;
 
-type CrcHashU32 = u32;
+const COMMON_FOOTER_SIZE: usize = 4 * 5;
 
 #[derive(Debug, Clone, PartialEq)]
 pub struct Footer {
-    pub version: Version,
+    pub tantivy_version: (u32, u32, u32),
     pub meta: String,
     pub versioned_footer: VersionedFooter,
 }
 
-/// Serialises the footer to a byte-array
-/// - versioned_footer_len : 4 bytes
-///-  versioned_footer: variable bytes
-/// - meta_len: 4 bytes
-/// - meta: variable bytes
-/// - version_len: 4 bytes
-/// - version json: variable bytes
-impl BinarySerializable for Footer {
-    fn serialize<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
-        BinarySerializable::serialize(&self.versioned_footer, writer)?;
-        BinarySerializable::serialize(&self.meta, writer)?;
-        let version_string =
-            serde_json::to_string(&self.version).map_err(|_err| io::ErrorKind::InvalidInput)?;
-        BinarySerializable::serialize(&version_string, writer)?;
-        Ok(())
-    }
-
-    fn deserialize<R: io::Read>(reader: &mut R) -> io::Result<Self> {
-        let versioned_footer = VersionedFooter::deserialize(reader)?;
-        let meta = String::deserialize(reader)?;
-        let version_json = String::deserialize(reader)?;
-        let version = serde_json::from_str(&version_json)?;
-        Ok(Footer {
-            version,
-            meta,
-            versioned_footer,
-        })
-    }
-}
-
 impl Footer {
     pub fn new(versioned_footer: VersionedFooter) -> Self {
-        let version = crate::VERSION.clone();
-        let meta = version.to_string();
+        let tantivy_version = (
+            env!("CARGO_PKG_VERSION_MAJOR").parse().unwrap(),
+            env!("CARGO_PKG_VERSION_MINOR").parse().unwrap(),
+            env!("CARGO_PKG_VERSION_PATCH").parse().unwrap(),
+        );
         Footer {
-            version,
-            meta,
+            tantivy_version,
+            meta: format!(
+                "tantivy {}.{}.{}, index v{}",
+                tantivy_version.0,
+                tantivy_version.1,
+                tantivy_version.2,
+                versioned_footer.version()
+            ),
             versioned_footer,
         }
     }
 
-    pub fn append_footer<W: io::Write>(&self, mut write: &mut W) -> io::Result<()> {
-        let mut counting_write = CountingWriter::wrap(&mut write);
-        self.serialize(&mut counting_write)?;
-        let written_len = counting_write.written_bytes();
-        write.write_u32::<LittleEndian>(written_len as u32)?;
-        Ok(())
+    pub fn to_bytes(&self) -> Vec<u8> {
+        let mut res = self.versioned_footer.to_bytes();
+        res.extend_from_slice(self.meta.as_bytes());
+        let len = res.len();
+        res.resize(len + COMMON_FOOTER_SIZE, 0);
+        let mut common_footer = &mut res[len..];
+        LittleEndian::write_u32(&mut common_footer, self.meta.len() as u32);
+        LittleEndian::write_u32(&mut common_footer[4..], self.tantivy_version.0);
+        LittleEndian::write_u32(&mut common_footer[8..], self.tantivy_version.1);
+        LittleEndian::write_u32(&mut common_footer[12..], self.tantivy_version.2);
+        LittleEndian::write_u32(&mut common_footer[16..], (len + COMMON_FOOTER_SIZE) as u32);
+        res
     }
 
-    pub fn extract_footer(source: ReadOnlySource) -> Result<(Footer, ReadOnlySource), io::Error> {
-        if source.len() < 4 {
+    pub fn from_bytes(data: &[u8]) -> Result<Self, io::Error> {
+        let len = data.len();
+        if len < COMMON_FOOTER_SIZE + 4 {
+            // 4 bytes for index version, stored in versioned footer
+            return Err(io::Error::new(
+                    io::ErrorKind::UnexpectedEof,
+                    format!("File corrupted. The footer len must be over 24, while the entire file len is {}", len)
+                    )
+            );
+        }
+
+        let size = LittleEndian::read_u32(&data[len - 4..]) as usize;
+        if len < size as usize {
             return Err(io::Error::new(
                 io::ErrorKind::UnexpectedEof,
                 format!(
-                    "File corrupted. The file is smaller than 4 bytes (len={}).",
-                    source.len()
+                    "File corrupted. The footer len is {}, while the entire file len is {}",
+                    size, len
                 ),
             ));
         }
-        let (body_footer, footer_len_bytes) = source.split_from_end(u32::SIZE_IN_BYTES);
-        let footer_len = LittleEndian::read_u32(footer_len_bytes.as_slice()) as usize;
-        let body_len = body_footer.len() - footer_len;
-        let (body, footer_data) = body_footer.split(body_len);
-        let mut cursor = footer_data.as_slice();
-        let footer = Footer::deserialize(&mut cursor)?;
-        Ok((footer, body))
+        let footer = &data[len - size as usize..];
+        let meta_len = LittleEndian::read_u32(&footer[size - 20..]) as usize;
+        let tantivy_major = LittleEndian::read_u32(&footer[size - 16..]);
+        let tantivy_minor = LittleEndian::read_u32(&footer[size - 12..]);
+        let tantivy_patch = LittleEndian::read_u32(&footer[size - 8..]);
+        Ok(Footer {
+            tantivy_version: (tantivy_major, tantivy_minor, tantivy_patch),
+            meta: String::from_utf8_lossy(&footer[size - meta_len - 20..size - 20]).into_owned(),
+            versioned_footer: VersionedFooter::from_bytes(&footer[..size - meta_len - 20])?,
+        })
     }
 
-    /// Confirms that the index will be read correctly by this version of tantivy
-    /// Has to be called after `extract_footer` to make sure it's not accessing uninitialised memory
-    pub fn is_compatible(&self) -> Result<(), Incompatibility> {
-        let library_version = crate::version();
-        match &self.versioned_footer {
-            VersionedFooter::V1 {
-                crc32: _crc,
-                store_compression: compression,
-            } => {
-                if &library_version.store_compression != compression {
-                    return Err(Incompatibility::CompressionMismatch {
-                        library_compression_format: library_version.store_compression.to_string(),
-                        index_compression_format: compression.to_string(),
-                    });
-                }
-                Ok(())
-            }
-            VersionedFooter::UnknownVersion => Err(Incompatibility::IndexMismatch {
-                library_version: library_version.clone(),
-                index_version: self.version.clone(),
-            }),
-        }
+    pub fn extract_footer(source: ReadOnlySource) -> Result<(Footer, ReadOnlySource), io::Error> {
+        let footer = Footer::from_bytes(source.as_slice())?;
+        let reader = source.slice_to(source.as_slice().len() - footer.size());
+        Ok((footer, reader))
+    }
+
+    pub fn size(&self) -> usize {
+        self.versioned_footer.size() as usize + self.meta.len() + 20
     }
 }
 
-/// Footer that includes a crc32 hash that enables us to checksum files in the index
 #[derive(Debug, Clone, PartialEq)]
 pub enum VersionedFooter {
-    UnknownVersion,
-    V1 {
-        crc32: CrcHashU32,
-        store_compression: String,
-    },
-}
-
-impl BinarySerializable for VersionedFooter {
-    fn serialize<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
-        let mut buf = Vec::new();
-        match self {
-            VersionedFooter::V1 {
-                crc32,
-                store_compression: compression,
-            } => {
-                // Serializes a valid `VersionedFooter` or panics if the version is unknown
-                // [   version    |   crc_hash  | compression_mode ]
-                // [    0..4      |     4..8    |     variable     ]
-                BinarySerializable::serialize(&1u32, &mut buf)?;
-                BinarySerializable::serialize(crc32, &mut buf)?;
-                BinarySerializable::serialize(compression, &mut buf)?;
-            }
-            VersionedFooter::UnknownVersion => {
-                return Err(io::Error::new(
-                    io::ErrorKind::InvalidInput,
-                    "Cannot serialize an unknown versioned footer ",
-                ));
-            }
-        }
-        BinarySerializable::serialize(&VInt(buf.len() as u64), writer)?;
-        writer.write_all(&buf[..])?;
-        Ok(())
-    }
-
-    fn deserialize<R: io::Read>(reader: &mut R) -> io::Result<Self> {
-        let len = VInt::deserialize(reader)?.0 as usize;
-        let mut buf = vec![0u8; len];
-        reader.read_exact(&mut buf[..])?;
-        let mut cursor = &buf[..];
-        let version = u32::deserialize(&mut cursor)?;
-        if version == 1 {
-            let crc32 = u32::deserialize(&mut cursor)?;
-            let compression = String::deserialize(&mut cursor)?;
-            Ok(VersionedFooter::V1 {
-                crc32,
-                store_compression: compression,
-            })
-        } else {
-            Ok(VersionedFooter::UnknownVersion)
-        }
-    }
+    UnknownVersion { version: u32, size: u32 },
+    V0(u32), // crc
 }
 
 impl VersionedFooter {
-    pub fn crc(&self) -> Option<CrcHashU32> {
+    pub fn to_bytes(&self) -> Vec<u8> {
         match self {
-            VersionedFooter::V1 { crc32, .. } => Some(*crc32),
+            VersionedFooter::V0(crc) => {
+                let mut res = vec![0; 8];
+                LittleEndian::write_u32(&mut res, 0);
+                LittleEndian::write_u32(&mut res[4..], *crc);
+                res
+            }
+            VersionedFooter::UnknownVersion { .. } => {
+                panic!("Unsupported index should never get serialized");
+            }
+        }
+    }
+
+    pub fn from_bytes(footer: &[u8]) -> Result<Self, io::Error> {
+        assert!(footer.len() >= 4);
+        let version = LittleEndian::read_u32(footer);
+        match version {
+            0 => {
+                if footer.len() == 8 {
+                    Ok(VersionedFooter::V0(LittleEndian::read_u32(&footer[4..])))
+                } else {
+                    Err(io::Error::new(
+                        io::ErrorKind::UnexpectedEof,
+                        format!(
+                            "File corrupted. The versioned footer len is {}, while it should be 8",
+                            footer.len()
+                        ),
+                    ))
+                }
+            }
+            version => Ok(VersionedFooter::UnknownVersion {
+                version,
+                size: footer.len() as u32,
+            }),
+        }
+    }
+
+    pub fn size(&self) -> u32 {
+        match self {
+            VersionedFooter::V0(_) => 8,
+            VersionedFooter::UnknownVersion { size, .. } => *size,
+        }
+    }
+
+    pub fn version(&self) -> u32 {
+        match self {
+            VersionedFooter::V0(_) => 0,
+            VersionedFooter::UnknownVersion { version, .. } => *version,
+        }
+    }
+
+    pub fn crc(&self) -> Option<u32> {
+        match self {
+            VersionedFooter::V0(crc) => Some(*crc),
             VersionedFooter::UnknownVersion { .. } => None,
         }
     }
@@ -205,135 +189,25 @@ impl<W: TerminatingWrite> Write for FooterProxy<W> {
 
 impl<W: TerminatingWrite> TerminatingWrite for FooterProxy<W> {
     fn terminate_ref(&mut self, _: AntiCallToken) -> io::Result<()> {
-        let crc32 = self.hasher.take().unwrap().finalize();
-        let footer = Footer::new(VersionedFooter::V1 {
-            crc32,
-            store_compression: crate::store::COMPRESSION.to_string(),
-        });
+        let crc = self.hasher.take().unwrap().finalize();
+
+        let footer = Footer::new(VersionedFooter::V0(crc)).to_bytes();
         let mut writer = self.writer.take().unwrap();
-        footer.append_footer(&mut writer)?;
+        writer.write_all(&footer)?;
         writer.terminate()
     }
 }
 
 #[cfg(test)]
 mod tests {
-
-    use super::CrcHashU32;
-    use super::FooterProxy;
-    use crate::common::BinarySerializable;
     use crate::directory::footer::{Footer, VersionedFooter};
-    use crate::directory::TerminatingWrite;
-    use byteorder::{ByteOrder, LittleEndian};
-    use regex::Regex;
-
-    #[test]
-    fn test_versioned_footer() {
-        let mut vec = Vec::new();
-        let footer_proxy = FooterProxy::new(&mut vec);
-        assert!(footer_proxy.terminate().is_ok());
-        assert_eq!(vec.len(), 167);
-        let footer = Footer::deserialize(&mut &vec[..]).unwrap();
-        if let VersionedFooter::V1 {
-            crc32: _,
-            store_compression,
-        } = footer.versioned_footer
-        {
-            assert_eq!(store_compression, crate::store::COMPRESSION);
-        } else {
-            panic!("Versioned footer should be V1.");
-        }
-        assert_eq!(&footer.version, crate::version());
-    }
 
     #[test]
     fn test_serialize_deserialize_footer() {
-        let mut buffer = Vec::new();
-        let crc32 = 123456u32;
-        let footer: Footer = Footer::new(VersionedFooter::V1 {
-            crc32,
-            store_compression: "lz4".to_string(),
-        });
-        footer.serialize(&mut buffer).unwrap();
-        let footer_deser = Footer::deserialize(&mut &buffer[..]).unwrap();
-        assert_eq!(footer_deser, footer);
-    }
+        let crc = 123456;
+        let footer = Footer::new(VersionedFooter::V0(crc));
+        let footer_bytes = footer.to_bytes();
 
-    #[test]
-    fn footer_length() {
-        let crc32 = 1111111u32;
-        let versioned_footer = VersionedFooter::V1 {
-            crc32,
-            store_compression: "lz4".to_string(),
-        };
-        let mut buf = Vec::new();
-        versioned_footer.serialize(&mut buf).unwrap();
-        assert_eq!(buf.len(), 13);
-        let footer = Footer::new(versioned_footer);
-        let regex_ptn = Regex::new(
-            "tantivy v[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.{0,10}, index_format v[0-9]{1,5}",
-        )
-        .unwrap();
-        assert!(regex_ptn.is_match(&footer.meta));
-    }
-
-    #[test]
-    fn versioned_footer_from_bytes() {
-        let v_footer_bytes = vec![
-            // versionned footer length
-            12 | 128,
-            // index format version
-            1,
-            0,
-            0,
-            0,
-            // crc 32
-            12,
-            35,
-            89,
-            18,
-            // compression format
-            3 | 128,
-            b'l',
-            b'z',
-            b'4',
-        ];
-        let mut cursor = &v_footer_bytes[..];
-        let versioned_footer = VersionedFooter::deserialize(&mut cursor).unwrap();
-        assert!(cursor.is_empty());
-        let expected_crc: u32 = LittleEndian::read_u32(&v_footer_bytes[5..9]) as CrcHashU32;
-        let expected_versioned_footer: VersionedFooter = VersionedFooter::V1 {
-            crc32: expected_crc,
-            store_compression: "lz4".to_string(),
-        };
-        assert_eq!(versioned_footer, expected_versioned_footer);
-        let mut buffer = Vec::new();
-        assert!(versioned_footer.serialize(&mut buffer).is_ok());
-        assert_eq!(&v_footer_bytes[..], &buffer[..]);
-    }
-
-    #[test]
-    fn versioned_footer_panic() {
-        let v_footer_bytes = vec![6u8 | 128u8, 3u8, 0u8, 0u8, 1u8, 0u8, 0u8];
-        let mut b = &v_footer_bytes[..];
-        let versioned_footer = VersionedFooter::deserialize(&mut b).unwrap();
-        assert!(b.is_empty());
-        let expected_versioned_footer = VersionedFooter::UnknownVersion;
-        assert_eq!(versioned_footer, expected_versioned_footer);
-        let mut buf = Vec::new();
-        assert!(versioned_footer.serialize(&mut buf).is_err());
-    }
-
-    #[test]
-    #[cfg(not(feature = "lz4"))]
-    fn compression_mismatch() {
-        let crc32 = 1111111u32;
-        let versioned_footer = VersionedFooter::V1 {
-            crc32,
-            store_compression: "lz4".to_string(),
-        };
-        let footer = Footer::new(versioned_footer);
-        let res = footer.is_compatible();
-        assert!(res.is_err());
+        assert_eq!(Footer::from_bytes(&footer_bytes).unwrap(), footer);
     }
 }

src/directory/managed_directory.rs

@@ -2,15 +2,13 @@ use crate::core::MANAGED_FILEPATH;
 use crate::directory::error::{DeleteError, IOError, LockError, OpenReadError, OpenWriteError};
 use crate::directory::footer::{Footer, FooterProxy};
 use crate::directory::DirectoryLock;
-use crate::directory::GarbageCollectionResult;
 use crate::directory::Lock;
 use crate::directory::META_LOCK;
 use crate::directory::{ReadOnlySource, WritePtr};
 use crate::directory::{WatchCallback, WatchHandle};
 use crate::error::DataCorruption;
 use crate::Directory;
-
-use crate::directory::directory::ReadOnlyDirectory;
+use crate::Result;
 use crc32fast::Hasher;
 use serde_json;
 use std::collections::HashSet;
@@ -66,7 +64,7 @@ fn save_managed_paths(
 
 impl ManagedDirectory {
     /// Wraps a directory as managed directory.
-    pub fn wrap<Dir: Directory>(directory: Dir) -> crate::Result<ManagedDirectory> {
+    pub fn wrap<Dir: Directory>(directory: Dir) -> Result<ManagedDirectory> {
         match directory.atomic_read(&MANAGED_FILEPATH) {
             Ok(data) => {
                 let managed_files_json = String::from_utf8_lossy(&data);
@@ -89,11 +87,6 @@ impl ManagedDirectory {
                 meta_informations: Arc::default(),
             }),
             Err(OpenReadError::IOError(e)) => Err(From::from(e)),
-            Err(OpenReadError::IncompatibleIndex(incompatibility)) => {
-                // For the moment, this should never happen  `meta.json`
-                // do not have any footer and cannot detect incompatibility.
-                Err(crate::TantivyError::IncompatibleIndex(incompatibility))
-            }
         }
     }
 
@@ -111,10 +104,7 @@ impl ManagedDirectory {
     /// If a file cannot be deleted (for permission reasons for instance)
     /// an error is simply logged, and the file remains in the list of managed
     /// files.
-    pub fn garbage_collect<L: FnOnce() -> HashSet<PathBuf>>(
-        &mut self,
-        get_living_files: L,
-    ) -> crate::Result<GarbageCollectionResult> {
+    pub fn garbage_collect<L: FnOnce() -> HashSet<PathBuf>>(&mut self, get_living_files: L) {
         info!("Garbage collect");
         let mut files_to_delete = vec![];
 
@@ -140,25 +130,19 @@ impl ManagedDirectory {
             // 2) writer change meta.json (for instance after a merge or a commit)
             // 3) gc kicks in.
             // 4) gc removes a file that was useful for process B, before process B opened it.
-            match self.acquire_lock(&META_LOCK) {
-                Ok(_meta_lock) => {
-                    let living_files = get_living_files();
-                    for managed_path in &meta_informations_rlock.managed_paths {
-                        if !living_files.contains(managed_path) {
-                            files_to_delete.push(managed_path.clone());
-                        }
+            if let Ok(_meta_lock) = self.acquire_lock(&META_LOCK) {
+                let living_files = get_living_files();
+                for managed_path in &meta_informations_rlock.managed_paths {
+                    if !living_files.contains(managed_path) {
+                        files_to_delete.push(managed_path.clone());
                     }
                 }
-                Err(err) => {
-                    error!("Failed to acquire lock for GC");
-                    return Err(crate::Error::from(err));
-                }
+            } else {
+                error!("Failed to acquire lock for GC");
             }
         }
 
-        let mut failed_to_delete_files = vec![];
         let mut deleted_files = vec![];
-
         for file_to_delete in files_to_delete {
             match self.delete(&file_to_delete) {
                 Ok(_) => {
@@ -168,10 +152,9 @@ impl ManagedDirectory {
                 Err(file_error) => {
                     match file_error {
                         DeleteError::FileDoesNotExist(_) => {
-                            deleted_files.push(file_to_delete.clone());
+                            deleted_files.push(file_to_delete);
                         }
                         DeleteError::IOError(_) => {
-                            failed_to_delete_files.push(file_to_delete.clone());
                             if !cfg!(target_os = "windows") {
                                 // On windows, delete is expected to fail if the file
                                 // is mmapped.
@@ -194,13 +177,10 @@ impl ManagedDirectory {
             for delete_file in &deleted_files {
                 managed_paths_write.remove(delete_file);
             }
-            save_managed_paths(self.directory.as_mut(), &meta_informations_wlock)?;
+            if save_managed_paths(self.directory.as_mut(), &meta_informations_wlock).is_err() {
+                error!("Failed to save the list of managed files.");
+            }
         }
-
-        Ok(GarbageCollectionResult {
-            deleted_files,
-            failed_to_delete_files,
-        })
     }
 
     /// Registers a file as managed
@@ -265,6 +245,13 @@ impl ManagedDirectory {
 }
 
 impl Directory for ManagedDirectory {
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
+        let read_only_source = self.directory.open_read(path)?;
+        let (_footer, reader) = Footer::extract_footer(read_only_source)
+            .map_err(|err| IOError::with_path(path.to_path_buf(), err))?;
+        Ok(reader)
+    }
+
     fn open_write(&mut self, path: &Path) -> result::Result<WritePtr, OpenWriteError> {
         self.register_file_as_managed(path)
             .map_err(|e| IOError::with_path(path.to_owned(), e))?;
@@ -282,10 +269,18 @@ impl Directory for ManagedDirectory {
         self.directory.atomic_write(path, data)
     }
 
+    fn atomic_read(&self, path: &Path) -> result::Result<Vec<u8>, OpenReadError> {
+        self.directory.atomic_read(path)
+    }
+
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError> {
         self.directory.delete(path)
     }
 
+    fn exists(&self, path: &Path) -> bool {
+        self.directory.exists(path)
+    }
+
     fn acquire_lock(&self, lock: &Lock) -> result::Result<DirectoryLock, LockError> {
         self.directory.acquire_lock(lock)
     }
@@ -295,24 +290,6 @@ impl Directory for ManagedDirectory {
     }
 }
 
-impl ReadOnlyDirectory for ManagedDirectory {
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
-        let read_only_source = self.directory.open_read(path)?;
-        let (footer, reader) = Footer::extract_footer(read_only_source)
-            .map_err(|err| IOError::with_path(path.to_path_buf(), err))?;
-        footer.is_compatible()?;
-        Ok(reader)
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        self.directory.exists(path)
-    }
-
-    fn atomic_read(&self, path: &Path) -> result::Result<Vec<u8>, OpenReadError> {
-        self.directory.atomic_read(path)
-    }
-}
-
 impl Clone for ManagedDirectory {
     fn clone(&self) -> ManagedDirectory {
         ManagedDirectory {
@@ -326,9 +303,7 @@ impl Clone for ManagedDirectory {
 #[cfg(test)]
 mod tests_mmap_specific {
 
-    use crate::directory::{
-        Directory, ManagedDirectory, MmapDirectory, ReadOnlyDirectory, TerminatingWrite,
-    };
+    use crate::directory::{Directory, ManagedDirectory, MmapDirectory, TerminatingWrite};
     use std::collections::HashSet;
     use std::fs::OpenOptions;
     use std::io::Write;
@@ -352,8 +327,9 @@ mod tests_mmap_specific {
                 .unwrap();
             assert!(managed_directory.exists(test_path1));
             assert!(managed_directory.exists(test_path2));
-            let living_files: HashSet<PathBuf> = [test_path1.to_owned()].iter().cloned().collect();
-            assert!(managed_directory.garbage_collect(|| living_files).is_ok());
+            let living_files: HashSet<PathBuf> =
+                [test_path1.to_owned()].into_iter().cloned().collect();
+            managed_directory.garbage_collect(|| living_files);
             assert!(managed_directory.exists(test_path1));
             assert!(!managed_directory.exists(test_path2));
         }
@@ -363,7 +339,7 @@ mod tests_mmap_specific {
             assert!(managed_directory.exists(test_path1));
             assert!(!managed_directory.exists(test_path2));
             let living_files: HashSet<PathBuf> = HashSet::new();
-            assert!(managed_directory.garbage_collect(|| living_files).is_ok());
+            managed_directory.garbage_collect(|| living_files);
             assert!(!managed_directory.exists(test_path1));
             assert!(!managed_directory.exists(test_path2));
         }
@@ -385,9 +361,7 @@ mod tests_mmap_specific {
         assert!(managed_directory.exists(test_path1));
 
         let _mmap_read = managed_directory.open_read(test_path1).unwrap();
-        assert!(managed_directory
-            .garbage_collect(|| living_files.clone())
-            .is_ok());
+        managed_directory.garbage_collect(|| living_files.clone());
         if cfg!(target_os = "windows") {
             // On Windows, gc should try and fail the file as it is mmapped.
             assert!(managed_directory.exists(test_path1));
@@ -395,7 +369,7 @@ mod tests_mmap_specific {
             drop(_mmap_read);
             // The file should still be in the list of managed file and
             // eventually be deleted once mmap is released.
-            assert!(managed_directory.garbage_collect(|| living_files).is_ok());
+            managed_directory.garbage_collect(|| living_files);
             assert!(!managed_directory.exists(test_path1));
         } else {
             assert!(!managed_directory.exists(test_path1));
@@ -420,8 +394,6 @@ mod tests_mmap_specific {
         write.write_all(&[3u8, 4u8, 5u8]).unwrap();
         write.terminate().unwrap();
 
-        let read_source = managed_directory.open_read(test_path2).unwrap();
-        assert_eq!(read_source.as_slice(), &[3u8, 4u8, 5u8]);
         assert!(managed_directory.list_damaged().unwrap().is_empty());
 
         let mut corrupted_path = tempdir_path.clone();

src/directory/mmap_directory.rs

@@ -6,7 +6,6 @@ use self::notify::RawEvent;
 use self::notify::RecursiveMode;
 use self::notify::Watcher;
 use crate::core::META_FILEPATH;
-use crate::directory::directory::ReadOnlyDirectory;
 use crate::directory::error::LockError;
 use crate::directory::error::{
     DeleteError, IOError, OpenDirectoryError, OpenReadError, OpenWriteError,
@@ -132,13 +131,14 @@ impl MmapCache {
         }
         self.cache.remove(full_path);
         self.counters.miss += 1;
-        let mmap_opt = open_mmap(full_path)?;
-        Ok(mmap_opt.map(|mmap| {
+        Ok(if let Some(mmap) = open_mmap(full_path)? {
             let mmap_arc: Arc<BoxedData> = Arc::new(Box::new(mmap));
             let mmap_weak = Arc::downgrade(&mmap_arc);
             self.cache.insert(full_path.to_owned(), mmap_weak);
-            mmap_arc
-        }))
+            Some(mmap_arc)
+        } else {
+            None
+        })
     }
 }
 
@@ -174,7 +174,7 @@ impl WatcherWrapper {
                             // We might want to be more accurate than this at one point.
                             if let Some(filename) = changed_path.file_name() {
                                 if filename == *META_FILEPATH {
-                                    let _ = watcher_router_clone.broadcast();
+                                    watcher_router_clone.broadcast();
                                 }
                             }
                         }
@@ -408,6 +408,24 @@ impl TerminatingWrite for SafeFileWriter {
 }
 
 impl Directory for MmapDirectory {
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
+        debug!("Open Read {:?}", path);
+        let full_path = self.resolve_path(path);
+
+        let mut mmap_cache = self.inner.mmap_cache.write().map_err(|_| {
+            let msg = format!(
+                "Failed to acquired write lock \
+                 on mmap cache while reading {:?}",
+                path
+            );
+            IOError::with_path(path.to_owned(), make_io_err(msg))
+        })?;
+        Ok(mmap_cache
+            .get_mmap(&full_path)?
+            .map(ReadOnlySource::from)
+            .unwrap_or_else(ReadOnlySource::empty))
+    }
+
     /// Any entry associated to the path in the mmap will be
     /// removed before the file is deleted.
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError> {
@@ -426,6 +444,11 @@ impl Directory for MmapDirectory {
         }
     }
 
+    fn exists(&self, path: &Path) -> bool {
+        let full_path = self.resolve_path(path);
+        full_path.exists()
+    }
+
     fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError> {
         debug!("Open Write {:?}", path);
         let full_path = self.resolve_path(path);
@@ -456,6 +479,25 @@ impl Directory for MmapDirectory {
         Ok(BufWriter::new(Box::new(writer)))
     }
 
+    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
+        let full_path = self.resolve_path(path);
+        let mut buffer = Vec::new();
+        match File::open(&full_path) {
+            Ok(mut file) => {
+                file.read_to_end(&mut buffer)
+                    .map_err(|e| IOError::with_path(path.to_owned(), e))?;
+                Ok(buffer)
+            }
+            Err(e) => {
+                if e.kind() == io::ErrorKind::NotFound {
+                    Err(OpenReadError::FileDoesNotExist(path.to_owned()))
+                } else {
+                    Err(IOError::with_path(path.to_owned(), e).into())
+                }
+            }
+        }
+    }
+
     fn atomic_write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
         debug!("Atomic Write {:?}", path);
         let full_path = self.resolve_path(path);
@@ -489,50 +531,6 @@ impl Directory for MmapDirectory {
     }
 }
 
-impl ReadOnlyDirectory for MmapDirectory {
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
-        debug!("Open Read {:?}", path);
-        let full_path = self.resolve_path(path);
-
-        let mut mmap_cache = self.inner.mmap_cache.write().map_err(|_| {
-            let msg = format!(
-                "Failed to acquired write lock \
-                 on mmap cache while reading {:?}",
-                path
-            );
-            IOError::with_path(path.to_owned(), make_io_err(msg))
-        })?;
-        Ok(mmap_cache
-            .get_mmap(&full_path)?
-            .map(ReadOnlySource::from)
-            .unwrap_or_else(ReadOnlySource::empty))
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        let full_path = self.resolve_path(path);
-        full_path.exists()
-    }
-
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
-        let full_path = self.resolve_path(path);
-        let mut buffer = Vec::new();
-        match File::open(&full_path) {
-            Ok(mut file) => {
-                file.read_to_end(&mut buffer)
-                    .map_err(|e| IOError::with_path(path.to_owned(), e))?;
-                Ok(buffer)
-            }
-            Err(e) => {
-                if e.kind() == io::ErrorKind::NotFound {
-                    Err(OpenReadError::FileDoesNotExist(path.to_owned()))
-                } else {
-                    Err(IOError::with_path(path.to_owned(), e).into())
-                }
-            }
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
 
@@ -540,15 +538,16 @@ mod tests {
     // The following tests are specific to the MmapDirectory
 
     use super::*;
-    use crate::indexer::LogMergePolicy;
     use crate::schema::{Schema, SchemaBuilder, TEXT};
     use crate::Index;
     use crate::ReloadPolicy;
     use std::fs;
     use std::sync::atomic::{AtomicUsize, Ordering};
+    use std::thread;
+    use std::time::Duration;
 
     #[test]
-    fn test_open_non_existent_path() {
+    fn test_open_non_existant_path() {
         assert!(MmapDirectory::open(PathBuf::from("./nowhere")).is_err());
     }
 
@@ -641,18 +640,13 @@ mod tests {
         let tmp_dir = tempfile::TempDir::new().unwrap();
         let tmp_dirpath = tmp_dir.path().to_owned();
         let mut watch_wrapper = WatcherWrapper::new(&tmp_dirpath).unwrap();
-        let tmp_file = tmp_dirpath.join(*META_FILEPATH);
+        let tmp_file = tmp_dirpath.join("coucou");
         let _handle = watch_wrapper.watch(Box::new(move || {
             counter_clone.fetch_add(1, Ordering::SeqCst);
         }));
-        let (sender, receiver) = crossbeam::channel::unbounded();
-        let _handle2 = watch_wrapper.watch(Box::new(move || {
-            let _ = sender.send(());
-        }));
         assert_eq!(counter.load(Ordering::SeqCst), 0);
         fs::write(&tmp_file, b"whateverwilldo").unwrap();
-        assert!(receiver.recv().is_ok());
-        assert!(counter.load(Ordering::SeqCst) >= 1);
+        thread::sleep(Duration::new(0, 1_000u32));
     }
 
     #[test]
@@ -661,42 +655,34 @@ mod tests {
         let mut schema_builder: SchemaBuilder = Schema::builder();
         let text_field = schema_builder.add_text_field("text", TEXT);
         let schema = schema_builder.build();
-
         {
             let index = Index::create(mmap_directory.clone(), schema).unwrap();
-
             let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-            let mut log_merge_policy = LogMergePolicy::default();
-            log_merge_policy.set_min_merge_size(3);
-            index_writer.set_merge_policy(Box::new(log_merge_policy));
-            for _num_commits in 0..10 {
+            for _num_commits in 0..16 {
                 for _ in 0..10 {
                     index_writer.add_document(doc!(text_field=>"abc"));
                 }
                 index_writer.commit().unwrap();
             }
-
             let reader = index
                 .reader_builder()
                 .reload_policy(ReloadPolicy::Manual)
                 .try_into()
                 .unwrap();
-
-            for _ in 0..4 {
+            for _ in 0..30 {
                 index_writer.add_document(doc!(text_field=>"abc"));
                 index_writer.commit().unwrap();
                 reader.reload().unwrap();
             }
             index_writer.wait_merging_threads().unwrap();
-
             reader.reload().unwrap();
             let num_segments = reader.searcher().segment_readers().len();
-            assert!(num_segments <= 4);
+            assert_eq!(num_segments, 4);
             assert_eq!(
                 num_segments * 7,
                 mmap_directory.get_cache_info().mmapped.len()
             );
         }
-        assert!(mmap_directory.get_cache_info().mmapped.is_empty());
+        assert_eq!(mmap_directory.get_cache_info().mmapped.len(), 0);
     }
 }

src/directory/mod.rs

@@ -7,7 +7,6 @@ WORM directory abstraction.
 #[cfg(feature = "mmap")]
 mod mmap_directory;
 
-mod bundle_directory;
 mod directory;
 mod directory_lock;
 mod footer;
@@ -20,26 +19,13 @@ mod watch_event_router;
 pub mod error;
 
 pub use self::directory::DirectoryLock;
-pub use self::directory::{Directory, DirectoryClone, ReadOnlyDirectory};
+pub use self::directory::{Directory, DirectoryClone};
 pub use self::directory_lock::{Lock, INDEX_WRITER_LOCK, META_LOCK};
 pub use self::ram_directory::RAMDirectory;
 pub use self::read_only_source::ReadOnlySource;
-pub use self::watch_event_router::{WatchCallback, WatchCallbackList, WatchHandle};
+pub(crate) use self::watch_event_router::WatchCallbackList;
+pub use self::watch_event_router::{WatchCallback, WatchHandle};
 use std::io::{self, BufWriter, Write};
-use std::path::PathBuf;
-/// Outcome of the Garbage collection
-pub struct GarbageCollectionResult {
-    /// List of files that were deleted in this cycle
-    pub deleted_files: Vec<PathBuf>,
-    /// List of files that were schedule to be deleted in this cycle,
-    /// but deletion did not work. This typically happens on windows,
-    /// as deleting a memory mapped file is forbidden.
-    ///
-    /// If a searcher is still held, a file cannot be deleted.
-    /// This is not considered a bug, the file will simply be deleted
-    /// in the next GC.
-    pub failed_to_delete_files: Vec<PathBuf>,
-}
 
 #[cfg(feature = "mmap")]
 pub use self::mmap_directory::MmapDirectory;
@@ -47,9 +33,6 @@ pub use self::mmap_directory::MmapDirectory;
 pub use self::managed_directory::ManagedDirectory;
 
 /// Struct used to prevent from calling [`terminate_ref`](trait.TerminatingWrite#method.terminate_ref) directly
-///
-/// The point is that while the type is public, it cannot be built by anyone
-/// outside of this module.
 pub struct AntiCallToken(());
 
 /// Trait used to indicate when no more write need to be done on a writer
@@ -80,13 +63,6 @@ impl<W: TerminatingWrite> TerminatingWrite for BufWriter<W> {
     }
 }
 
-#[cfg(test)]
-impl<'a> TerminatingWrite for &'a mut Vec<u8> {
-    fn terminate_ref(&mut self, _a: AntiCallToken) -> io::Result<()> {
-        self.flush()
-    }
-}
-
 /// Write object for Directory.
 ///
 /// `WritePtr` are required to implement both Write

src/directory/ram_directory.rs

@@ -1,6 +1,4 @@
-use crate::common::CountingWriter;
 use crate::core::META_FILEPATH;
-use crate::directory::directory::ReadOnlyDirectory;
 use crate::directory::error::{DeleteError, OpenReadError, OpenWriteError};
 use crate::directory::AntiCallToken;
 use crate::directory::WatchCallbackList;
@@ -117,22 +115,6 @@ impl InnerDirectory {
     fn total_mem_usage(&self) -> usize {
         self.fs.values().map(|f| f.len()).sum()
     }
-
-    fn serialize_bundle(&self, wrt: &mut WritePtr) -> io::Result<()> {
-        let mut counting_writer = CountingWriter::wrap(wrt);
-        let mut file_index: HashMap<PathBuf, (u64, u64)> = HashMap::default();
-        for (path, source) in &self.fs {
-            let start = counting_writer.written_bytes();
-            counting_writer.write_all(source.as_slice())?;
-            let stop = counting_writer.written_bytes();
-            file_index.insert(path.to_path_buf(), (start, stop));
-        }
-        let index_offset = counting_writer.written_bytes();
-        serde_json::to_writer(&mut counting_writer, &file_index)?;
-        let index_offset_buffer = index_offset.to_le_bytes();
-        counting_writer.write_all(&index_offset_buffer[..])?;
-        Ok(())
-    }
 }
 
 impl fmt::Debug for RAMDirectory {
@@ -162,18 +144,13 @@ impl RAMDirectory {
     pub fn total_mem_usage(&self) -> usize {
         self.fs.read().unwrap().total_mem_usage()
     }
-
-    /// Serialize the RAMDirectory into a bundle.
-    ///
-    /// This method will fail, write nothing, and return an error if a
-    /// clone of this repository exists.
-    pub fn serialize_bundle(self, wrt: &mut WritePtr) -> io::Result<()> {
-        let inner_directory_rlock = self.fs.read().unwrap();
-        inner_directory_rlock.serialize_bundle(wrt)
-    }
 }
 
 impl Directory for RAMDirectory {
+    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
+        self.fs.read().unwrap().open_read(path)
+    }
+
     fn delete(&self, path: &Path) -> result::Result<(), DeleteError> {
         fail_point!("RAMDirectory::delete", |_| {
             use crate::directory::error::IOError;
@@ -183,6 +160,10 @@ impl Directory for RAMDirectory {
         self.fs.write().unwrap().delete(path)
     }
 
+    fn exists(&self, path: &Path) -> bool {
+        self.fs.read().unwrap().exists(path)
+    }
+
     fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError> {
         let mut fs = self.fs.write().unwrap();
         let path_buf = PathBuf::from(path);
@@ -196,6 +177,10 @@ impl Directory for RAMDirectory {
         }
     }
 
+    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
+        Ok(self.open_read(path)?.as_slice().to_owned())
+    }
+
     fn atomic_write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
         fail_point!("RAMDirectory::atomic_write", |msg| Err(io::Error::new(
             io::ErrorKind::Other,
@@ -206,11 +191,11 @@ impl Directory for RAMDirectory {
         // Reserve the path to prevent calls to .write() to succeed.
         self.fs.write().unwrap().write(path_buf.clone(), &[]);
 
-        let mut vec_writer = VecWriter::new(path_buf, self.clone());
+        let mut vec_writer = VecWriter::new(path_buf.clone(), self.clone());
         vec_writer.write_all(data)?;
         vec_writer.flush()?;
         if path == Path::new(&*META_FILEPATH) {
-            let _ = self.fs.write().unwrap().watch_router.broadcast();
+            self.fs.write().unwrap().watch_router.broadcast();
         }
         Ok(())
     }
@@ -219,17 +204,3 @@ impl Directory for RAMDirectory {
         Ok(self.fs.write().unwrap().watch(watch_callback))
     }
 }
-
-impl ReadOnlyDirectory for RAMDirectory {
-    fn open_read(&self, path: &Path) -> result::Result<ReadOnlySource, OpenReadError> {
-        self.fs.read().unwrap().open_read(path)
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        self.fs.read().unwrap().exists(path)
-    }
-
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
-        Ok(self.open_read(path)?.as_slice().to_owned())
-    }
-}

src/directory/read_only_source.rs

@@ -70,12 +70,6 @@ impl ReadOnlySource {
         (left, right)
     }
 
-    /// Splits into 2 `ReadOnlySource`, at the offset `end - right_len`.
-    pub fn split_from_end(self, right_len: usize) -> (ReadOnlySource, ReadOnlySource) {
-        let left_len = self.len() - right_len;
-        self.split(left_len)
-    }
-
     /// Creates a ReadOnlySource that is just a
     /// view over a slice of the data.
     ///

src/directory/tests.rs

@@ -1,117 +1,25 @@
 use super::*;
-use futures::channel::oneshot;
-use futures::executor::block_on;
 use std::io::Write;
 use std::mem;
 use std::path::{Path, PathBuf};
-use std::sync::atomic::Ordering::SeqCst;
-use std::sync::atomic::{AtomicBool, AtomicUsize};
+use std::sync::atomic::AtomicUsize;
+use std::sync::atomic::Ordering;
 use std::sync::Arc;
+use std::thread;
+use std::time;
 use std::time::Duration;
 
-#[cfg(feature = "mmap")]
-mod mmap_directory_tests {
-    use crate::directory::MmapDirectory;
-
-    type DirectoryImpl = MmapDirectory;
-
-    fn make_directory() -> DirectoryImpl {
-        MmapDirectory::create_from_tempdir().unwrap()
-    }
-
-    #[test]
-    fn test_simple() {
-        let mut directory = make_directory();
-        super::test_simple(&mut directory);
-    }
-
-    #[test]
-    fn test_write_create_the_file() {
-        let mut directory = make_directory();
-        super::test_write_create_the_file(&mut directory);
-    }
-
-    #[test]
-    fn test_rewrite_forbidden() {
-        let mut directory = make_directory();
-        super::test_rewrite_forbidden(&mut directory);
-    }
-
-    #[test]
-    fn test_directory_delete() {
-        let mut directory = make_directory();
-        super::test_directory_delete(&mut directory);
-    }
-
-    #[test]
-    fn test_lock_non_blocking() {
-        let mut directory = make_directory();
-        super::test_lock_non_blocking(&mut directory);
-    }
-
-    #[test]
-    fn test_lock_blocking() {
-        let mut directory = make_directory();
-        super::test_lock_blocking(&mut directory);
-    }
-
-    #[test]
-    fn test_watch() {
-        let mut directory = make_directory();
-        super::test_watch(&mut directory);
-    }
+#[test]
+fn test_ram_directory() {
+    let mut ram_directory = RAMDirectory::create();
+    test_directory(&mut ram_directory);
 }
 
-mod ram_directory_tests {
-    use crate::directory::RAMDirectory;
-
-    type DirectoryImpl = RAMDirectory;
-
-    fn make_directory() -> DirectoryImpl {
-        RAMDirectory::default()
-    }
-
-    #[test]
-    fn test_simple() {
-        let mut directory = make_directory();
-        super::test_simple(&mut directory);
-    }
-
-    #[test]
-    fn test_write_create_the_file() {
-        let mut directory = make_directory();
-        super::test_write_create_the_file(&mut directory);
-    }
-
-    #[test]
-    fn test_rewrite_forbidden() {
-        let mut directory = make_directory();
-        super::test_rewrite_forbidden(&mut directory);
-    }
-
-    #[test]
-    fn test_directory_delete() {
-        let mut directory = make_directory();
-        super::test_directory_delete(&mut directory);
-    }
-
-    #[test]
-    fn test_lock_non_blocking() {
-        let mut directory = make_directory();
-        super::test_lock_non_blocking(&mut directory);
-    }
-
-    #[test]
-    fn test_lock_blocking() {
-        let mut directory = make_directory();
-        super::test_lock_blocking(&mut directory);
-    }
-
-    #[test]
-    fn test_watch() {
-        let mut directory = make_directory();
-        super::test_watch(&mut directory);
-    }
+#[test]
+#[cfg(feature = "mmap")]
+fn test_mmap_directory() {
+    let mut mmap_directory = MmapDirectory::create_from_tempdir().unwrap();
+    test_directory(&mut mmap_directory);
 }
 
 #[test]
@@ -191,39 +99,48 @@ fn test_directory_delete(directory: &mut dyn Directory) {
     assert!(directory.delete(&test_path).is_err());
 }
 
+fn test_directory(directory: &mut dyn Directory) {
+    test_simple(directory);
+    test_rewrite_forbidden(directory);
+    test_write_create_the_file(directory);
+    test_directory_delete(directory);
+    test_lock_non_blocking(directory);
+    test_lock_blocking(directory);
+    test_watch(directory);
+}
+
 fn test_watch(directory: &mut dyn Directory) {
-    let num_progress: Arc<AtomicUsize> = Default::default();
     let counter: Arc<AtomicUsize> = Default::default();
     let counter_clone = counter.clone();
-    let (sender, receiver) = crossbeam::channel::unbounded();
     let watch_callback = Box::new(move || {
-        counter_clone.fetch_add(1, SeqCst);
+        counter_clone.fetch_add(1, Ordering::SeqCst);
     });
-    // This callback is used to synchronize watching in our unit test.
-    // We bind it to a variable because the callback is removed when that
-    // handle is dropped.
-    let watch_handle = directory.watch(watch_callback).unwrap();
-    let _progress_listener = directory
-        .watch(Box::new(move || {
-            let val = num_progress.fetch_add(1, SeqCst);
-            let _ = sender.send(val);
-        }))
-        .unwrap();
+    assert!(directory
+        .atomic_write(Path::new("meta.json"), b"random_test_data")
+        .is_ok());
+    thread::sleep(Duration::new(0, 10_000));
+    assert_eq!(0, counter.load(Ordering::SeqCst));
 
+    let watch_handle = directory.watch(watch_callback).unwrap();
     for i in 0..10 {
-        assert_eq!(i, counter.load(SeqCst));
+        assert_eq!(i, counter.load(Ordering::SeqCst));
         assert!(directory
             .atomic_write(Path::new("meta.json"), b"random_test_data_2")
             .is_ok());
-        assert_eq!(receiver.recv_timeout(Duration::from_millis(500)), Ok(i));
-        assert_eq!(i + 1, counter.load(SeqCst));
+        for _ in 0..1_000 {
+            if counter.load(Ordering::SeqCst) > i {
+                break;
+            }
+            thread::sleep(Duration::from_millis(10));
+        }
+        assert_eq!(i + 1, counter.load(Ordering::SeqCst));
     }
     mem::drop(watch_handle);
     assert!(directory
         .atomic_write(Path::new("meta.json"), b"random_test_data")
         .is_ok());
-    assert!(receiver.recv_timeout(Duration::from_millis(500)).is_ok());
-    assert_eq!(10, counter.load(SeqCst));
+    thread::sleep(Duration::from_millis(200));
+    assert_eq!(10, counter.load(Ordering::SeqCst));
 }
 
 fn test_lock_non_blocking(directory: &mut dyn Directory) {
@@ -257,13 +174,9 @@ fn test_lock_blocking(directory: &mut dyn Directory) {
         is_blocking: true,
     });
     assert!(lock_a_res.is_ok());
-    let in_thread = Arc::new(AtomicBool::default());
-    let in_thread_clone = in_thread.clone();
-    let (sender, receiver) = oneshot::channel();
     std::thread::spawn(move || {
         //< lock_a_res is sent to the thread.
-        in_thread_clone.store(true, SeqCst);
-        let _just_sync = block_on(receiver);
+        std::thread::sleep(time::Duration::from_millis(10));
         // explicitely droping lock_a_res. It would have been sufficient to just force it
         // to be part of the move, but the intent seems clearer that way.
         drop(lock_a_res);
@@ -276,18 +189,14 @@ fn test_lock_blocking(directory: &mut dyn Directory) {
         });
         assert!(lock_a_res.is_err());
     }
-    let directory_clone = directory.box_clone();
-    let (sender2, receiver2) = oneshot::channel();
-    let join_handle = std::thread::spawn(move || {
-        assert!(sender2.send(()).is_ok());
-        let lock_a_res = directory_clone.acquire_lock(&Lock {
+    {
+        // the blocking call should wait for at least 10ms.
+        let start = time::Instant::now();
+        let lock_a_res = directory.acquire_lock(&Lock {
             filepath: PathBuf::from("a.lock"),
             is_blocking: true,
         });
-        assert!(in_thread.load(SeqCst));
         assert!(lock_a_res.is_ok());
-    });
-    assert!(block_on(receiver2).is_ok());
-    assert!(sender.send(()).is_ok());
-    assert!(join_handle.join().is_ok());
+        assert!(start.elapsed().subsec_millis() >= 10);
+    }
 }

src/directory/watch_event_router.rs

@@ -1,5 +1,3 @@
-use futures::channel::oneshot;
-use futures::{Future, TryFutureExt};
 use std::sync::Arc;
 use std::sync::RwLock;
 use std::sync::Weak;
@@ -24,20 +22,13 @@ pub struct WatchCallbackList {
 #[derive(Clone)]
 pub struct WatchHandle(Arc<WatchCallback>);
 
-impl WatchHandle {
-    /// Create a WatchHandle handle.
-    pub fn new(watch_callback: Arc<WatchCallback>) -> WatchHandle {
-        WatchHandle(watch_callback)
-    }
-}
-
 impl WatchCallbackList {
     /// Suscribes a new callback and returns a handle that controls the lifetime of the callback.
     pub fn subscribe(&self, watch_callback: WatchCallback) -> WatchHandle {
         let watch_callback_arc = Arc::new(watch_callback);
         let watch_callback_weak = Arc::downgrade(&watch_callback_arc);
         self.router.write().unwrap().push(watch_callback_weak);
-        WatchHandle::new(watch_callback_arc)
+        WatchHandle(watch_callback_arc)
     }
 
     fn list_callback(&self) -> Vec<Arc<WatchCallback>> {
@@ -56,21 +47,14 @@ impl WatchCallbackList {
     }
 
     /// Triggers all callbacks
-    pub fn broadcast(&self) -> impl Future<Output = ()> {
+    pub fn broadcast(&self) {
         let callbacks = self.list_callback();
-        let (sender, receiver) = oneshot::channel();
-        let result = receiver.unwrap_or_else(|_| ());
-        if callbacks.is_empty() {
-            let _ = sender.send(());
-            return result;
-        }
         let spawn_res = std::thread::Builder::new()
             .name("watch-callbacks".to_string())
             .spawn(move || {
                 for callback in callbacks {
                     callback();
                 }
-                let _ = sender.send(());
             });
         if let Err(err) = spawn_res {
             error!(
@@ -78,17 +62,19 @@ impl WatchCallbackList {
                 err
             );
         }
-        result
     }
 }
 
 #[cfg(test)]
 mod tests {
     use crate::directory::WatchCallbackList;
-    use futures::executor::block_on;
     use std::mem;
     use std::sync::atomic::{AtomicUsize, Ordering};
     use std::sync::Arc;
+    use std::thread;
+    use std::time::Duration;
+
+    const WAIT_TIME: u64 = 20;
 
     #[test]
     fn test_watch_event_router_simple() {
@@ -98,22 +84,22 @@ mod tests {
         let inc_callback = Box::new(move || {
             counter_clone.fetch_add(1, Ordering::SeqCst);
         });
-        block_on(watch_event_router.broadcast());
+        watch_event_router.broadcast();
         assert_eq!(0, counter.load(Ordering::SeqCst));
         let handle_a = watch_event_router.subscribe(inc_callback);
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(0, counter.load(Ordering::SeqCst));
-        block_on(watch_event_router.broadcast());
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(1, counter.load(Ordering::SeqCst));
-        block_on(async {
-            (
-                watch_event_router.broadcast().await,
-                watch_event_router.broadcast().await,
-                watch_event_router.broadcast().await,
-            )
-        });
+        watch_event_router.broadcast();
+        watch_event_router.broadcast();
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(4, counter.load(Ordering::SeqCst));
         mem::drop(handle_a);
-        block_on(watch_event_router.broadcast());
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(4, counter.load(Ordering::SeqCst));
     }
 
@@ -129,20 +115,20 @@ mod tests {
         };
         let handle_a = watch_event_router.subscribe(inc_callback(1));
         let handle_a2 = watch_event_router.subscribe(inc_callback(10));
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(0, counter.load(Ordering::SeqCst));
-        block_on(async {
-            futures::join!(
-                watch_event_router.broadcast(),
-                watch_event_router.broadcast()
-            )
-        });
+        watch_event_router.broadcast();
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(22, counter.load(Ordering::SeqCst));
         mem::drop(handle_a);
-        block_on(watch_event_router.broadcast());
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(32, counter.load(Ordering::SeqCst));
         mem::drop(handle_a2);
-        block_on(watch_event_router.broadcast());
-        block_on(watch_event_router.broadcast());
+        watch_event_router.broadcast();
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(32, counter.load(Ordering::SeqCst));
     }
 
@@ -156,15 +142,14 @@ mod tests {
         });
         let handle_a = watch_event_router.subscribe(inc_callback);
         assert_eq!(0, counter.load(Ordering::SeqCst));
-        block_on(async {
-            let future1 = watch_event_router.broadcast();
-            let future2 = watch_event_router.broadcast();
-            futures::join!(future1, future2)
-        });
+        watch_event_router.broadcast();
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(2, counter.load(Ordering::SeqCst));
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         mem::drop(handle_a);
-        let _ = watch_event_router.broadcast();
-        block_on(watch_event_router.broadcast());
+        watch_event_router.broadcast();
+        thread::sleep(Duration::from_millis(WAIT_TIME));
         assert_eq!(2, counter.load(Ordering::SeqCst));
     }
 }

src/error.rs

@@ -2,8 +2,8 @@
 
 use std::io;
 
+use crate::directory::error::LockError;
 use crate::directory::error::{IOError, OpenDirectoryError, OpenReadError, OpenWriteError};
-use crate::directory::error::{Incompatibility, LockError};
 use crate::fastfield::FastFieldNotAvailableError;
 use crate::query;
 use crate::schema;
@@ -25,10 +25,10 @@ impl DataCorruption {
         }
     }
 
-    pub fn comment_only<TS: ToString>(comment: TS) -> DataCorruption {
+    pub fn comment_only(comment: String) -> DataCorruption {
         DataCorruption {
             filepath: None,
-            comment: comment.to_string(),
+            comment,
         }
     }
 }
@@ -80,9 +80,6 @@ pub enum TantivyError {
     /// System error. (e.g.: We failed spawning a new thread)
     #[fail(display = "System error.'{}'", _0)]
     SystemError(String),
-    /// Index incompatible with current version of tantivy
-    #[fail(display = "{:?}", _0)]
-    IncompatibleIndex(Incompatibility),
 }
 
 impl From<DataCorruption> for TantivyError {
@@ -132,9 +129,6 @@ impl From<OpenReadError> for TantivyError {
         match error {
             OpenReadError::FileDoesNotExist(filepath) => TantivyError::PathDoesNotExist(filepath),
             OpenReadError::IOError(io_error) => TantivyError::IOError(io_error),
-            OpenReadError::IncompatibleIndex(incompatibility) => {
-                TantivyError::IncompatibleIndex(incompatibility)
-            }
         }
     }
 }
@@ -176,9 +170,3 @@ impl From<serde_json::Error> for TantivyError {
         TantivyError::IOError(io_err.into())
     }
 }
-
-impl From<rayon::ThreadPoolBuildError> for TantivyError {
-    fn from(error: rayon::ThreadPoolBuildError) -> TantivyError {
-        TantivyError::SystemError(error.to_string())
-    }
-}

src/fastfield/delete.rs

@@ -1,19 +1,17 @@
-use crate::common::{BitSet, HasLen};
+use crate::common::HasLen;
 use crate::directory::ReadOnlySource;
 use crate::directory::WritePtr;
 use crate::space_usage::ByteCount;
 use crate::DocId;
+use bit_set::BitSet;
 use std::io;
 use std::io::Write;
 
 /// Write a delete `BitSet`
 ///
 /// where `delete_bitset` is the set of deleted `DocId`.
-pub fn write_delete_bitset(
-    delete_bitset: &BitSet,
-    max_doc: u32,
-    writer: &mut WritePtr,
-) -> io::Result<()> {
+pub fn write_delete_bitset(delete_bitset: &BitSet, writer: &mut WritePtr) -> io::Result<()> {
+    let max_doc = delete_bitset.capacity();
     let mut byte = 0u8;
     let mut shift = 0u8;
     for doc in 0..max_doc {
@@ -31,7 +29,7 @@ pub fn write_delete_bitset(
     if max_doc % 8 > 0 {
         writer.write_all(&[byte])?;
     }
-    Ok(())
+    writer.flush()
 }
 
 /// Set of deleted `DocId`s.
@@ -85,40 +83,43 @@ impl HasLen for DeleteBitSet {
 mod tests {
     use super::*;
     use crate::directory::*;
+    use bit_set::BitSet;
     use std::path::PathBuf;
 
-    fn test_delete_bitset_helper(bitset: &BitSet, max_doc: u32) {
+    fn test_delete_bitset_helper(bitset: &BitSet) {
         let test_path = PathBuf::from("test");
         let mut directory = RAMDirectory::create();
         {
             let mut writer = directory.open_write(&*test_path).unwrap();
-            write_delete_bitset(bitset, max_doc, &mut writer).unwrap();
-            writer.terminate().unwrap();
+            write_delete_bitset(bitset, &mut writer).unwrap();
         }
-        let source = directory.open_read(&test_path).unwrap();
-        let delete_bitset = DeleteBitSet::open(source);
-        for doc in 0..max_doc {
-            assert_eq!(bitset.contains(doc), delete_bitset.is_deleted(doc as DocId));
+        {
+            let source = directory.open_read(&test_path).unwrap();
+            let delete_bitset = DeleteBitSet::open(source);
+            let n = bitset.capacity();
+            for doc in 0..n {
+                assert_eq!(bitset.contains(doc), delete_bitset.is_deleted(doc as DocId));
+            }
+            assert_eq!(delete_bitset.len(), bitset.len());
         }
-        assert_eq!(delete_bitset.len(), bitset.len());
     }
 
     #[test]
     fn test_delete_bitset() {
         {
-            let mut bitset = BitSet::with_max_value(10);
+            let mut bitset = BitSet::with_capacity(10);
             bitset.insert(1);
             bitset.insert(9);
-            test_delete_bitset_helper(&bitset, 10);
+            test_delete_bitset_helper(&bitset);
         }
         {
-            let mut bitset = BitSet::with_max_value(8);
+            let mut bitset = BitSet::with_capacity(8);
             bitset.insert(1);
             bitset.insert(2);
             bitset.insert(3);
             bitset.insert(5);
             bitset.insert(7);
-            test_delete_bitset_helper(&bitset, 8);
+            test_delete_bitset_helper(&bitset);
         }
     }
 }

src/fastfield/mod.rs

@@ -33,7 +33,6 @@ pub use self::reader::FastFieldReader;
 pub use self::readers::FastFieldReaders;
 pub use self::serializer::FastFieldSerializer;
 pub use self::writer::{FastFieldsWriter, IntFastFieldWriter};
-use crate::chrono::{NaiveDateTime, Utc};
 use crate::common;
 use crate::schema::Cardinality;
 use crate::schema::FieldType;
@@ -50,7 +49,7 @@ mod serializer;
 mod writer;
 
 /// Trait for types that are allowed for fast fields: (u64, i64 and f64).
-pub trait FastValue: Clone + Copy + Send + Sync + PartialOrd {
+pub trait FastValue: Default + Clone + Copy + Send + Sync + PartialOrd {
     /// Converts a value from u64
     ///
     /// Internally all fast field values are encoded as u64.
@@ -70,12 +69,6 @@ pub trait FastValue: Clone + Copy + Send + Sync + PartialOrd {
     /// Cast value to `u64`.
     /// The value is just reinterpreted in memory.
     fn as_u64(&self) -> u64;
-
-    /// Build a default value. This default value is never used, so the value does not
-    /// really matter.
-    fn make_zero() -> Self {
-        Self::from_u64(0i64.to_u64())
-    }
 }
 
 impl FastValue for u64 {
@@ -142,34 +135,11 @@ impl FastValue for f64 {
     }
 }
 
-impl FastValue for crate::DateTime {
-    fn from_u64(timestamp_u64: u64) -> Self {
-        let timestamp_i64 = i64::from_u64(timestamp_u64);
-        crate::DateTime::from_utc(NaiveDateTime::from_timestamp(timestamp_i64, 0), Utc)
-    }
-
-    fn to_u64(&self) -> u64 {
-        self.timestamp().to_u64()
-    }
-
-    fn fast_field_cardinality(field_type: &FieldType) -> Option<Cardinality> {
-        match *field_type {
-            FieldType::Date(ref integer_options) => integer_options.get_fastfield_cardinality(),
-            _ => None,
-        }
-    }
-
-    fn as_u64(&self) -> u64 {
-        self.timestamp().as_u64()
-    }
-}
-
 fn value_to_u64(value: &Value) -> u64 {
     match *value {
         Value::U64(ref val) => *val,
         Value::I64(ref val) => common::i64_to_u64(*val),
         Value::F64(ref val) => common::f64_to_u64(*val),
-        Value::Date(ref datetime) => common::i64_to_u64(datetime.timestamp()),
         _ => panic!("Expected a u64/i64/f64 field, got {:?} ", value),
     }
 }
@@ -179,14 +149,12 @@ mod tests {
 
     use super::*;
     use crate::common::CompositeFile;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, WritePtr};
+    use crate::directory::{Directory, RAMDirectory, WritePtr};
     use crate::fastfield::FastFieldReader;
-    use crate::merge_policy::NoMergePolicy;
+    use crate::schema::Document;
     use crate::schema::Field;
     use crate::schema::Schema;
     use crate::schema::FAST;
-    use crate::schema::{Document, IntOptions};
-    use crate::{Index, SegmentId, SegmentReader};
     use once_cell::sync::Lazy;
     use rand::prelude::SliceRandom;
     use rand::rngs::StdRng;
@@ -210,12 +178,6 @@ mod tests {
         assert_eq!(test_fastfield.get(2), 300);
     }
 
-    #[test]
-    pub fn test_fastfield_i64_u64() {
-        let datetime = crate::DateTime::from_utc(NaiveDateTime::from_timestamp(0i64, 0), Utc);
-        assert_eq!(i64::from_u64(datetime.to_u64()), 0i64);
-    }
-
     #[test]
     fn test_intfastfield_small() {
         let path = Path::new("test");
@@ -467,93 +429,6 @@ mod tests {
             }
         }
     }
-
-    #[test]
-    fn test_merge_missing_date_fast_field() {
-        let mut schema_builder = Schema::builder();
-        let date_field = schema_builder.add_date_field("date", FAST);
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        index_writer.set_merge_policy(Box::new(NoMergePolicy));
-        index_writer.add_document(doc!(date_field =>crate::chrono::prelude::Utc::now()));
-        index_writer.commit().unwrap();
-        index_writer.add_document(doc!());
-        index_writer.commit().unwrap();
-        let reader = index.reader().unwrap();
-        let segment_ids: Vec<SegmentId> = reader
-            .searcher()
-            .segment_readers()
-            .iter()
-            .map(SegmentReader::segment_id)
-            .collect();
-        assert_eq!(segment_ids.len(), 2);
-        let merge_future = index_writer.merge(&segment_ids[..]);
-        let merge_res = futures::executor::block_on(merge_future);
-        assert!(merge_res.is_ok());
-        assert!(reader.reload().is_ok());
-        assert_eq!(reader.searcher().segment_readers().len(), 1);
-    }
-
-    #[test]
-    fn test_default_datetime() {
-        assert_eq!(crate::DateTime::make_zero().timestamp(), 0i64);
-    }
-
-    #[test]
-    fn test_datefastfield() {
-        use crate::fastfield::FastValue;
-        let mut schema_builder = Schema::builder();
-        let date_field = schema_builder.add_date_field("date", FAST);
-        let multi_date_field = schema_builder.add_date_field(
-            "multi_date",
-            IntOptions::default().set_fast(Cardinality::MultiValues),
-        );
-        let schema = schema_builder.build();
-        let index = Index::create_in_ram(schema);
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        index_writer.set_merge_policy(Box::new(NoMergePolicy));
-        index_writer.add_document(doc!(
-            date_field => crate::DateTime::from_u64(1i64.to_u64()),
-            multi_date_field => crate::DateTime::from_u64(2i64.to_u64()),
-            multi_date_field => crate::DateTime::from_u64(3i64.to_u64())
-        ));
-        index_writer.add_document(doc!(
-            date_field => crate::DateTime::from_u64(4i64.to_u64())
-        ));
-        index_writer.add_document(doc!(
-            multi_date_field => crate::DateTime::from_u64(5i64.to_u64()),
-            multi_date_field => crate::DateTime::from_u64(6i64.to_u64())
-        ));
-        index_writer.commit().unwrap();
-        let reader = index.reader().unwrap();
-        let searcher = reader.searcher();
-        assert_eq!(searcher.segment_readers().len(), 1);
-        let segment_reader = searcher.segment_reader(0);
-        let fast_fields = segment_reader.fast_fields();
-        let date_fast_field = fast_fields.date(date_field).unwrap();
-        let dates_fast_field = fast_fields.dates(multi_date_field).unwrap();
-        let mut dates = vec![];
-        {
-            assert_eq!(date_fast_field.get(0u32).timestamp(), 1i64);
-            dates_fast_field.get_vals(0u32, &mut dates);
-            assert_eq!(dates.len(), 2);
-            assert_eq!(dates[0].timestamp(), 2i64);
-            assert_eq!(dates[1].timestamp(), 3i64);
-        }
-        {
-            assert_eq!(date_fast_field.get(1u32).timestamp(), 4i64);
-            dates_fast_field.get_vals(1u32, &mut dates);
-            assert!(dates.is_empty());
-        }
-        {
-            assert_eq!(date_fast_field.get(2u32).timestamp(), 0i64);
-            dates_fast_field.get_vals(2u32, &mut dates);
-            assert_eq!(dates.len(), 2);
-            assert_eq!(dates[0].timestamp(), 5i64);
-            assert_eq!(dates[1].timestamp(), 6i64);
-        }
-    }
 }
 
 #[cfg(all(test, feature = "unstable"))]

src/fastfield/multivalued/reader.rs

@@ -45,7 +45,7 @@ impl<Item: FastValue> MultiValueIntFastFieldReader<Item> {
     pub fn get_vals(&self, doc: DocId, vals: &mut Vec<Item>) {
         let (start, stop) = self.range(doc);
         let len = (stop - start) as usize;
-        vals.resize(len, Item::make_zero());
+        vals.resize(len, Item::default());
         self.vals_reader.get_range_u64(start, &mut vals[..]);
     }
 

src/fastfield/reader.rs

@@ -4,7 +4,7 @@ use crate::common::compute_num_bits;
 use crate::common::BinarySerializable;
 use crate::common::CompositeFile;
 use crate::directory::ReadOnlySource;
-use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, WritePtr};
+use crate::directory::{Directory, RAMDirectory, WritePtr};
 use crate::fastfield::{FastFieldSerializer, FastFieldsWriter};
 use crate::schema::Schema;
 use crate::schema::FAST;

src/fastfield/readers.rs

@@ -15,11 +15,9 @@ pub struct FastFieldReaders {
     fast_field_i64: HashMap<Field, FastFieldReader<i64>>,
     fast_field_u64: HashMap<Field, FastFieldReader<u64>>,
     fast_field_f64: HashMap<Field, FastFieldReader<f64>>,
-    fast_field_date: HashMap<Field, FastFieldReader<crate::DateTime>>,
     fast_field_i64s: HashMap<Field, MultiValueIntFastFieldReader<i64>>,
     fast_field_u64s: HashMap<Field, MultiValueIntFastFieldReader<u64>>,
     fast_field_f64s: HashMap<Field, MultiValueIntFastFieldReader<f64>>,
-    fast_field_dates: HashMap<Field, MultiValueIntFastFieldReader<crate::DateTime>>,
     fast_bytes: HashMap<Field, BytesFastFieldReader>,
     fast_fields_composite: CompositeFile,
 }
@@ -28,7 +26,6 @@ enum FastType {
     I64,
     U64,
     F64,
-    Date,
 }
 
 fn type_and_cardinality(field_type: &FieldType) -> Option<(FastType, Cardinality)> {
@@ -42,9 +39,6 @@ fn type_and_cardinality(field_type: &FieldType) -> Option<(FastType, Cardinality
         FieldType::F64(options) => options
             .get_fastfield_cardinality()
             .map(|cardinality| (FastType::F64, cardinality)),
-        FieldType::Date(options) => options
-            .get_fastfield_cardinality()
-            .map(|cardinality| (FastType::Date, cardinality)),
         FieldType::HierarchicalFacet => Some((FastType::U64, Cardinality::MultiValues)),
         _ => None,
     }
@@ -59,11 +53,9 @@ impl FastFieldReaders {
             fast_field_i64: Default::default(),
             fast_field_u64: Default::default(),
             fast_field_f64: Default::default(),
-            fast_field_date: Default::default(),
             fast_field_i64s: Default::default(),
             fast_field_u64s: Default::default(),
             fast_field_f64s: Default::default(),
-            fast_field_dates: Default::default(),
             fast_bytes: Default::default(),
             fast_fields_composite: fast_fields_composite.clone(),
         };
@@ -103,12 +95,6 @@ impl FastFieldReaders {
                                         FastFieldReader::open(fast_field_data.clone()),
                                     );
                                 }
-                                FastType::Date => {
-                                    fast_field_readers.fast_field_date.insert(
-                                        field,
-                                        FastFieldReader::open(fast_field_data.clone()),
-                                    );
-                                }
                             }
                         } else {
                             return Err(From::from(FastFieldNotAvailableError::new(field_entry)));
@@ -144,14 +130,6 @@ impl FastFieldReaders {
                                         .fast_field_f64s
                                         .insert(field, multivalued_int_fast_field);
                                 }
-                                FastType::Date => {
-                                    let vals_reader = FastFieldReader::open(fast_field_data);
-                                    let multivalued_int_fast_field =
-                                        MultiValueIntFastFieldReader::open(idx_reader, vals_reader);
-                                    fast_field_readers
-                                        .fast_field_dates
-                                        .insert(field, multivalued_int_fast_field);
-                                }
                             }
                         } else {
                             return Err(From::from(FastFieldNotAvailableError::new(field_entry)));
@@ -178,6 +156,8 @@ impl FastFieldReaders {
     /// If the field is a i64-fast field, return the associated u64 reader. Values are
     /// mapped from i64 to u64 using a (well the, it is unique) monotonic mapping.    ///
     ///
+    ///TODO should it also be lenient with f64?
+    ///
     /// This method is useful when merging segment reader.
     pub(crate) fn u64_lenient(&self, field: Field) -> Option<FastFieldReader<u64>> {
         if let Some(u64_ff_reader) = self.u64(field) {
@@ -186,12 +166,6 @@ impl FastFieldReaders {
         if let Some(i64_ff_reader) = self.i64(field) {
             return Some(i64_ff_reader.into_u64_reader());
         }
-        if let Some(f64_ff_reader) = self.f64(field) {
-            return Some(f64_ff_reader.into_u64_reader());
-        }
-        if let Some(date_ff_reader) = self.date(field) {
-            return Some(date_ff_reader.into_u64_reader());
-        }
         None
     }
 
@@ -202,13 +176,6 @@ impl FastFieldReaders {
         self.fast_field_i64.get(&field).cloned()
     }
 
-    /// Returns the `i64` fast field reader reader associated to `field`.
-    ///
-    /// If `field` is not a i64 fast field, this method returns `None`.
-    pub fn date(&self, field: Field) -> Option<FastFieldReader<crate::DateTime>> {
-        self.fast_field_date.get(&field).cloned()
-    }
-
     /// Returns the `f64` fast field reader reader associated to `field`.
     ///
     /// If `field` is not a f64 fast field, this method returns `None`.
@@ -235,9 +202,6 @@ impl FastFieldReaders {
         if let Some(i64s_ff_reader) = self.i64s(field) {
             return Some(i64s_ff_reader.into_u64s_reader());
         }
-        if let Some(f64s_ff_reader) = self.f64s(field) {
-            return Some(f64s_ff_reader.into_u64s_reader());
-        }
         None
     }
 
@@ -255,13 +219,6 @@ impl FastFieldReaders {
         self.fast_field_f64s.get(&field).cloned()
     }
 
-    /// Returns a `crate::DateTime` multi-valued fast field reader reader associated to `field`.
-    ///
-    /// If `field` is not a `crate::DateTime` multi-valued fast field, this method returns `None`.
-    pub fn dates(&self, field: Field) -> Option<MultiValueIntFastFieldReader<crate::DateTime>> {
-        self.fast_field_dates.get(&field).cloned()
-    }
-
     /// Returns the `bytes` fast field reader associated to `field`.
     ///
     /// If `field` is not a bytes fast field, returns `None`.

src/fastfield/writer.rs

@@ -4,7 +4,7 @@ use crate::common::BinarySerializable;
 use crate::common::VInt;
 use crate::fastfield::{BytesFastFieldWriter, FastFieldSerializer};
 use crate::postings::UnorderedTermId;
-use crate::schema::{Cardinality, Document, Field, FieldEntry, FieldType, Schema};
+use crate::schema::{Cardinality, Document, Field, FieldType, Schema};
 use crate::termdict::TermOrdinal;
 use fnv::FnvHashMap;
 use std::collections::HashMap;
@@ -17,14 +17,6 @@ pub struct FastFieldsWriter {
     bytes_value_writers: Vec<BytesFastFieldWriter>,
 }
 
-fn fast_field_default_value(field_entry: &FieldEntry) -> u64 {
-    match *field_entry.field_type() {
-        FieldType::I64(_) | FieldType::Date(_) => common::i64_to_u64(0i64),
-        FieldType::F64(_) => common::f64_to_u64(0.0f64),
-        _ => 0u64,
-    }
-}
-
 impl FastFieldsWriter {
     /// Create all `FastFieldWriter` required by the schema.
     pub fn from_schema(schema: &Schema) -> FastFieldsWriter {
@@ -33,15 +25,18 @@ impl FastFieldsWriter {
         let mut bytes_value_writers = Vec::new();
 
         for (field, field_entry) in schema.fields() {
+            let default_value = match *field_entry.field_type() {
+                FieldType::I64(_) => common::i64_to_u64(0i64),
+                FieldType::F64(_) => common::f64_to_u64(0.0f64),
+                _ => 0u64,
+            };
             match *field_entry.field_type() {
                 FieldType::I64(ref int_options)
                 | FieldType::U64(ref int_options)
-                | FieldType::F64(ref int_options)
-                | FieldType::Date(ref int_options) => {
+                | FieldType::F64(ref int_options) => {
                     match int_options.get_fastfield_cardinality() {
                         Some(Cardinality::SingleValue) => {
                             let mut fast_field_writer = IntFastFieldWriter::new(field);
-                            let default_value = fast_field_default_value(field_entry);
                             fast_field_writer.set_val_if_missing(default_value);
                             single_value_writers.push(fast_field_writer);
                         }

src/indexer/delete_queue.rs

@@ -2,7 +2,7 @@ use super::operation::DeleteOperation;
 use crate::Opstamp;
 use std::mem;
 use std::ops::DerefMut;
-use std::sync::{Arc, RwLock, Weak};
+use std::sync::{Arc, RwLock};
 
 // The DeleteQueue is similar in conceptually to a multiple
 // consumer single producer broadcast channel.
@@ -14,15 +14,14 @@ use std::sync::{Arc, RwLock, Weak};
 //
 // New consumer can be created in two ways
 // - calling `delete_queue.cursor()` returns a cursor, that
-//   will include all future delete operation (and some or none
-//   of the past operations... The client is in charge of checking the opstamps.).
+//   will include all future delete operation (and no past operations).
 // - cloning an existing cursor returns a new cursor, that
 //   is at the exact same position, and can now advance independently
 //   from the original cursor.
 #[derive(Default)]
 struct InnerDeleteQueue {
     writer: Vec<DeleteOperation>,
-    last_block: Weak<Block>,
+    last_block: Option<Arc<Block>>,
 }
 
 #[derive(Clone)]
@@ -33,31 +32,21 @@ pub struct DeleteQueue {
 impl DeleteQueue {
     // Creates a new delete queue.
     pub fn new() -> DeleteQueue {
-        DeleteQueue {
+        let delete_queue = DeleteQueue {
             inner: Arc::default(),
-        }
-    }
+        };
+
+        let next_block = NextBlock::from(delete_queue.clone());
 
-    fn get_last_block(&self) -> Arc<Block> {
         {
-            // try get the last block with simply acquiring the read lock.
-            let rlock = self.inner.read().unwrap();
-            if let Some(block) = rlock.last_block.upgrade() {
-                return block;
-            }
+            let mut delete_queue_wlock = delete_queue.inner.write().unwrap();
+            delete_queue_wlock.last_block = Some(Arc::new(Block {
+                operations: Arc::default(),
+                next: next_block,
+            }));
         }
-        // It failed. Let's double check after acquiring the write, as someone could have called
-        // `get_last_block` right after we released the rlock.
-        let mut wlock = self.inner.write().unwrap();
-        if let Some(block) = wlock.last_block.upgrade() {
-            return block;
-        }
-        let block = Arc::new(Block {
-            operations: Arc::default(),
-            next: NextBlock::from(self.clone()),
-        });
-        wlock.last_block = Arc::downgrade(&block);
-        block
+
+        delete_queue
     }
 
     // Creates a new cursor that makes it possible to
@@ -65,7 +54,17 @@ impl DeleteQueue {
     //
     // Past delete operations are not accessible.
     pub fn cursor(&self) -> DeleteCursor {
-        let last_block = self.get_last_block();
+        let last_block = self
+            .inner
+            .read()
+            .expect("Read lock poisoned when opening delete queue cursor")
+            .last_block
+            .clone()
+            .expect(
+                "Failed to unwrap last_block. This should never happen
+                as the Option<> is only here to make
+                initialization possible",
+            );
         let operations_len = last_block.operations.len();
         DeleteCursor {
             block: last_block,
@@ -101,19 +100,23 @@ impl DeleteQueue {
             .write()
             .expect("Failed to acquire write lock on delete queue writer");
 
-        if self_wlock.writer.is_empty() {
-            return None;
+        let delete_operations;
+        {
+            let writer: &mut Vec<DeleteOperation> = &mut self_wlock.writer;
+            if writer.is_empty() {
+                return None;
+            }
+            delete_operations = mem::replace(writer, vec![]);
         }
 
-        let delete_operations = mem::replace(&mut self_wlock.writer, vec![]);
-
-        let new_block = Arc::new(Block {
-            operations: Arc::new(delete_operations.into_boxed_slice()),
-            next: NextBlock::from(self.clone()),
-        });
-
-        self_wlock.last_block = Arc::downgrade(&new_block);
-        Some(new_block)
+        let next_block = NextBlock::from(self.clone());
+        {
+            self_wlock.last_block = Some(Arc::new(Block {
+                operations: Arc::new(delete_operations),
+                next: next_block,
+            }));
+        }
+        self_wlock.last_block.clone()
     }
 }
 
@@ -167,7 +170,7 @@ impl NextBlock {
 }
 
 struct Block {
-    operations: Arc<Box<[DeleteOperation]>>,
+    operations: Arc<Vec<DeleteOperation>>,
     next: NextBlock,
 }
 

src/indexer/index_writer.rs

@@ -1,15 +1,14 @@
 use super::operation::{AddOperation, UserOperation};
 use super::segment_updater::SegmentUpdater;
 use super::PreparedCommit;
-use crate::common::BitSet;
 use crate::core::Index;
 use crate::core::Segment;
 use crate::core::SegmentComponent;
 use crate::core::SegmentId;
 use crate::core::SegmentMeta;
 use crate::core::SegmentReader;
+use crate::directory::DirectoryLock;
 use crate::directory::TerminatingWrite;
-use crate::directory::{DirectoryLock, GarbageCollectionResult};
 use crate::docset::DocSet;
 use crate::error::TantivyError;
 use crate::fastfield::write_delete_bitset;
@@ -24,9 +23,10 @@ use crate::schema::Document;
 use crate::schema::IndexRecordOption;
 use crate::schema::Term;
 use crate::Opstamp;
+use crate::Result;
+use bit_set::BitSet;
 use crossbeam::channel;
-use futures::executor::block_on;
-use futures::future::Future;
+use futures::{Canceled, Future};
 use smallvec::smallvec;
 use smallvec::SmallVec;
 use std::mem;
@@ -72,7 +72,7 @@ pub struct IndexWriter {
 
     heap_size_in_bytes_per_thread: usize,
 
-    workers_join_handle: Vec<JoinHandle<crate::Result<()>>>,
+    workers_join_handle: Vec<JoinHandle<Result<()>>>,
 
     operation_receiver: OperationReceiver,
     operation_sender: OperationSender,
@@ -95,7 +95,7 @@ fn compute_deleted_bitset(
     delete_cursor: &mut DeleteCursor,
     doc_opstamps: &DocToOpstampMapping,
     target_opstamp: Opstamp,
-) -> crate::Result<bool> {
+) -> Result<bool> {
     let mut might_have_changed = false;
     while let Some(delete_op) = delete_cursor.get() {
         if delete_op.opstamp > target_opstamp {
@@ -115,7 +115,7 @@ fn compute_deleted_bitset(
             while docset.advance() {
                 let deleted_doc = docset.doc();
                 if deleted_doc < limit_doc {
-                    delete_bitset.insert(deleted_doc);
+                    delete_bitset.insert(deleted_doc as usize);
                     might_have_changed = true;
                 }
             }
@@ -126,73 +126,65 @@ fn compute_deleted_bitset(
     Ok(might_have_changed)
 }
 
-/// Advance delete for the given segment up to the target opstamp.
-///
-/// Note that there are no guarantee that the resulting `segment_entry` delete_opstamp
-/// is `==` target_opstamp.
-/// For instance, there was no delete operation between the state of the `segment_entry` and
-/// the `target_opstamp`, `segment_entry` is not updated.
+/// Advance delete for the given segment up
+/// to the target opstamp.
 pub(crate) fn advance_deletes(
     mut segment: Segment,
     segment_entry: &mut SegmentEntry,
     target_opstamp: Opstamp,
-) -> crate::Result<()> {
-    if segment_entry.meta().delete_opstamp() == Some(target_opstamp) {
-        // We are already up-to-date here.
-        return Ok(());
-    }
+) -> Result<()> {
+    {
+        if segment_entry.meta().delete_opstamp() == Some(target_opstamp) {
+            // We are already up-to-date here.
+            return Ok(());
+        }
 
-    if segment_entry.delete_bitset().is_none() && segment_entry.delete_cursor().get().is_none() {
-        // There has been no `DeleteOperation` between the segment status and `target_opstamp`.
-        return Ok(());
-    }
+        let segment_reader = SegmentReader::open(&segment)?;
 
-    let segment_reader = SegmentReader::open(&segment)?;
+        let max_doc = segment_reader.max_doc();
+        let mut delete_bitset: BitSet = match segment_entry.delete_bitset() {
+            Some(previous_delete_bitset) => (*previous_delete_bitset).clone(),
+            None => BitSet::with_capacity(max_doc as usize),
+        };
 
-    let max_doc = segment_reader.max_doc();
-    let mut delete_bitset: BitSet = match segment_entry.delete_bitset() {
-        Some(previous_delete_bitset) => (*previous_delete_bitset).clone(),
-        None => BitSet::with_max_value(max_doc),
-    };
+        let delete_cursor = segment_entry.delete_cursor();
 
-    compute_deleted_bitset(
-        &mut delete_bitset,
-        &segment_reader,
-        segment_entry.delete_cursor(),
-        &DocToOpstampMapping::None,
-        target_opstamp,
-    )?;
+        compute_deleted_bitset(
+            &mut delete_bitset,
+            &segment_reader,
+            delete_cursor,
+            &DocToOpstampMapping::None,
+            target_opstamp,
+        )?;
 
-    // TODO optimize
-    if let Some(seg_delete_bitset) = segment_reader.delete_bitset() {
+        // TODO optimize
         for doc in 0u32..max_doc {
-            if seg_delete_bitset.is_deleted(doc) {
-                delete_bitset.insert(doc);
+            if segment_reader.is_deleted(doc) {
+                delete_bitset.insert(doc as usize);
             }
         }
-    }
 
-    let num_deleted_docs = delete_bitset.len();
-    if num_deleted_docs > 0 {
-        segment = segment.with_delete_meta(num_deleted_docs as u32, target_opstamp);
-        let mut delete_file = segment.open_write(SegmentComponent::DELETE)?;
-        write_delete_bitset(&delete_bitset, max_doc, &mut delete_file)?;
-        delete_file.terminate()?;
+        let num_deleted_docs = delete_bitset.len();
+        if num_deleted_docs > 0 {
+            segment = segment.with_delete_meta(num_deleted_docs as u32, target_opstamp);
+            let mut delete_file = segment.open_write(SegmentComponent::DELETE)?;
+            write_delete_bitset(&delete_bitset, &mut delete_file)?;
+            delete_file.terminate()?;
+        }
     }
-
     segment_entry.set_meta(segment.meta().clone());
     Ok(())
 }
 
 fn index_documents(
     memory_budget: usize,
-    segment: Segment,
+    segment: &Segment,
     grouped_document_iterator: &mut dyn Iterator<Item = OperationGroup>,
     segment_updater: &mut SegmentUpdater,
     mut delete_cursor: DeleteCursor,
-) -> crate::Result<bool> {
+) -> Result<bool> {
     let schema = segment.schema();
-
+    let segment_id = segment.id();
     let mut segment_writer = SegmentWriter::for_segment(memory_budget, segment.clone(), &schema)?;
     for document_group in grouped_document_iterator {
         for doc in document_group {
@@ -212,32 +204,22 @@ fn index_documents(
         return Ok(false);
     }
 
-    let max_doc = segment_writer.max_doc();
+    let num_docs = segment_writer.max_doc();
 
     // this is ensured by the call to peek before starting
     // the worker thread.
-    assert!(max_doc > 0);
+    assert!(num_docs > 0);
 
     let doc_opstamps: Vec<Opstamp> = segment_writer.finalize()?;
-
-    let segment_with_max_doc = segment.with_max_doc(max_doc);
+    let segment_meta = segment.index().new_segment_meta(segment_id, num_docs);
 
     let last_docstamp: Opstamp = *(doc_opstamps.last().unwrap());
 
-    let delete_bitset_opt = apply_deletes(
-        &segment_with_max_doc,
-        &mut delete_cursor,
-        &doc_opstamps,
-        last_docstamp,
-    )?;
+    let delete_bitset_opt =
+        apply_deletes(&segment, &mut delete_cursor, &doc_opstamps, last_docstamp)?;
 
-    let segment_entry = SegmentEntry::new(
-        segment_with_max_doc.meta().clone(),
-        delete_cursor,
-        delete_bitset_opt,
-    );
-    block_on(segment_updater.schedule_add_segment(segment_entry))?;
-    Ok(true)
+    let segment_entry = SegmentEntry::new(segment_meta, delete_cursor, delete_bitset_opt);
+    Ok(segment_updater.add_segment(segment_entry))
 }
 
 fn apply_deletes(
@@ -245,7 +227,7 @@ fn apply_deletes(
     mut delete_cursor: &mut DeleteCursor,
     doc_opstamps: &[Opstamp],
     last_docstamp: Opstamp,
-) -> crate::Result<Option<BitSet>> {
+) -> Result<Option<BitSet<u32>>> {
     if delete_cursor.get().is_none() {
         // if there are no delete operation in the queue, no need
         // to even open the segment.
@@ -253,9 +235,7 @@ fn apply_deletes(
     }
     let segment_reader = SegmentReader::open(segment)?;
     let doc_to_opstamps = DocToOpstampMapping::from(doc_opstamps);
-
-    let max_doc = segment.meta().max_doc();
-    let mut deleted_bitset = BitSet::with_max_value(max_doc);
+    let mut deleted_bitset = BitSet::with_capacity(segment_reader.max_doc() as usize);
     let may_have_deletes = compute_deleted_bitset(
         &mut deleted_bitset,
         &segment_reader,
@@ -290,7 +270,7 @@ impl IndexWriter {
         num_threads: usize,
         heap_size_in_bytes_per_thread: usize,
         directory_lock: DirectoryLock,
-    ) -> crate::Result<IndexWriter> {
+    ) -> Result<IndexWriter> {
         if heap_size_in_bytes_per_thread < HEAP_SIZE_MIN {
             let err_msg = format!(
                 "The heap size per thread needs to be at least {}.",
@@ -339,17 +319,12 @@ impl IndexWriter {
         Ok(index_writer)
     }
 
-    fn drop_sender(&mut self) {
-        let (sender, _receiver) = channel::bounded(1);
-        mem::replace(&mut self.operation_sender, sender);
-    }
-
     /// If there are some merging threads, blocks until they all finish their work and
     /// then drop the `IndexWriter`.
-    pub fn wait_merging_threads(mut self) -> crate::Result<()> {
+    pub fn wait_merging_threads(mut self) -> Result<()> {
         // this will stop the indexing thread,
         // dropping the last reference to the segment_updater.
-        self.drop_sender();
+        drop(self.operation_sender);
 
         let former_workers_handles = mem::replace(&mut self.workers_join_handle, vec![]);
         for join_handle in former_workers_handles {
@@ -360,6 +335,7 @@ impl IndexWriter {
                     TantivyError::ErrorInThread("Error in indexing worker thread.".into())
                 })?;
         }
+        drop(self.workers_join_handle);
 
         let result = self
             .segment_updater
@@ -374,10 +350,10 @@ impl IndexWriter {
     }
 
     #[doc(hidden)]
-    pub fn add_segment(&self, segment_meta: SegmentMeta) -> crate::Result<()> {
+    pub fn add_segment(&mut self, segment_meta: SegmentMeta) {
         let delete_cursor = self.delete_queue.cursor();
         let segment_entry = SegmentEntry::new(segment_meta, delete_cursor, None);
-        block_on(self.segment_updater.schedule_add_segment(segment_entry))
+        self.segment_updater.add_segment(segment_entry);
     }
 
     /// Creates a new segment.
@@ -394,7 +370,7 @@ impl IndexWriter {
 
     /// Spawns a new worker thread for indexing.
     /// The thread consumes documents from the pipeline.
-    fn add_indexing_worker(&mut self) -> crate::Result<()> {
+    fn add_indexing_worker(&mut self) -> Result<()> {
         let document_receiver_clone = self.operation_receiver.clone();
         let mut segment_updater = self.segment_updater.clone();
 
@@ -402,7 +378,7 @@ impl IndexWriter {
 
         let mem_budget = self.heap_size_in_bytes_per_thread;
         let index = self.index.clone();
-        let join_handle: JoinHandle<crate::Result<()>> = thread::Builder::new()
+        let join_handle: JoinHandle<Result<()>> = thread::Builder::new()
             .name(format!("thrd-tantivy-index{}", self.worker_id))
             .spawn(move || {
                 loop {
@@ -431,7 +407,7 @@ impl IndexWriter {
                     let segment = index.new_segment();
                     index_documents(
                         mem_budget,
-                        segment,
+                        &segment,
                         &mut document_iterator,
                         &mut segment_updater,
                         delete_cursor.clone(),
@@ -448,23 +424,22 @@ impl IndexWriter {
         self.segment_updater.get_merge_policy()
     }
 
-    /// Setter for the merge policy.
+    /// Set the merge policy.
     pub fn set_merge_policy(&self, merge_policy: Box<dyn MergePolicy>) {
         self.segment_updater.set_merge_policy(merge_policy);
     }
 
-    fn start_workers(&mut self) -> crate::Result<()> {
+    fn start_workers(&mut self) -> Result<()> {
         for _ in 0..self.num_threads {
             self.add_indexing_worker()?;
         }
         Ok(())
     }
 
-    /// Detects and removes the files that are not used by the index anymore.
-    pub fn garbage_collect_files(
-        &self,
-    ) -> impl Future<Output = crate::Result<GarbageCollectionResult>> {
-        self.segment_updater.schedule_garbage_collect()
+    /// Detects and removes the files that
+    /// are not used by the index anymore.
+    pub fn garbage_collect_files(&mut self) -> Result<()> {
+        self.segment_updater.garbage_collect_files().wait()
     }
 
     /// Deletes all documents from the index
@@ -503,7 +478,7 @@ impl IndexWriter {
     ///     Ok(())
     /// }
     /// ```
-    pub fn delete_all_documents(&self) -> crate::Result<Opstamp> {
+    pub fn delete_all_documents(&mut self) -> Result<Opstamp> {
         // Delete segments
         self.segment_updater.remove_all_segments();
         // Return new stamp - reverted stamp
@@ -517,10 +492,8 @@ impl IndexWriter {
     pub fn merge(
         &mut self,
         segment_ids: &[SegmentId],
-    ) -> impl Future<Output = crate::Result<SegmentMeta>> {
-        let merge_operation = self.segment_updater.make_merge_operation(segment_ids);
-        let segment_updater = self.segment_updater.clone();
-        async move { segment_updater.start_merge(merge_operation)?.await }
+    ) -> Result<impl Future<Item = SegmentMeta, Error = Canceled>> {
+        self.segment_updater.start_merge(segment_ids)
     }
 
     /// Closes the current document channel send.
@@ -546,8 +519,13 @@ impl IndexWriter {
     /// state as it was after the last commit.
     ///
     /// The opstamp at the last commit is returned.
-    pub fn rollback(&mut self) -> crate::Result<Opstamp> {
+    pub fn rollback(&mut self) -> Result<Opstamp> {
         info!("Rolling back to opstamp {}", self.committed_opstamp);
+        self.rollback_impl()
+    }
+
+    /// Private, implementation of rollback
+    fn rollback_impl(&mut self) -> Result<Opstamp> {
         // marks the segment updater as killed. From now on, all
         // segment updates will be ignored.
         self.segment_updater.kill();
@@ -603,7 +581,7 @@ impl IndexWriter {
     /// It is also possible to add a payload to the `commit`
     /// using this API.
     /// See [`PreparedCommit::set_payload()`](PreparedCommit.html)
-    pub fn prepare_commit(&mut self) -> crate::Result<PreparedCommit> {
+    pub fn prepare_commit(&mut self) -> Result<PreparedCommit<'_>> {
         // Here, because we join all of the worker threads,
         // all of the segment update for this commit have been
         // sent.
@@ -650,7 +628,7 @@ impl IndexWriter {
     /// Commit returns the `opstamp` of the last document
     /// that made it in the commit.
     ///
-    pub fn commit(&mut self) -> crate::Result<Opstamp> {
+    pub fn commit(&mut self) -> Result<Opstamp> {
         self.prepare_commit()?.commit()
     }
 
@@ -691,6 +669,9 @@ impl IndexWriter {
     /// The opstamp is an increasing `u64` that can
     /// be used by the client to align commits with its own
     /// document queue.
+    ///
+    /// Currently it represents the number of documents that
+    /// have been added since the creation of the index.
     pub fn add_document(&self, document: Document) -> Opstamp {
         let opstamp = self.stamper.stamp();
         let add_operation = AddOperation { opstamp, document };
@@ -764,16 +745,6 @@ impl IndexWriter {
     }
 }
 
-impl Drop for IndexWriter {
-    fn drop(&mut self) {
-        self.segment_updater.kill();
-        self.drop_sender();
-        for work in self.workers_join_handle.drain(..) {
-            let _ = work.join();
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
 
@@ -783,7 +754,7 @@ mod tests {
     use crate::error::*;
     use crate::indexer::NoMergePolicy;
     use crate::query::TermQuery;
-    use crate::schema::{self, IndexRecordOption, STRING};
+    use crate::schema::{self, IndexRecordOption};
     use crate::Index;
     use crate::ReloadPolicy;
     use crate::Term;
@@ -1208,16 +1179,4 @@ mod tests {
         assert!(clear_again.is_ok());
         assert!(commit_again.is_ok());
     }
-
-    #[test]
-    fn test_index_doc_missing_field() {
-        let mut schema_builder = schema::Schema::builder();
-        let idfield = schema_builder.add_text_field("id", STRING);
-        schema_builder.add_text_field("optfield", STRING);
-        let index = Index::create_in_ram(schema_builder.build());
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        index_writer.add_document(doc!(idfield=>"myid"));
-        let commit = index_writer.commit();
-        assert!(commit.is_ok());
-    }
 }

src/indexer/merge_operation.rs

@@ -2,23 +2,14 @@ use crate::Opstamp;
 use crate::SegmentId;
 use census::{Inventory, TrackedObject};
 use std::collections::HashSet;
-use std::ops::Deref;
 
 #[derive(Default)]
-pub(crate) struct MergeOperationInventory(Inventory<InnerMergeOperation>);
-
-impl Deref for MergeOperationInventory {
-    type Target = Inventory<InnerMergeOperation>;
-
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
+pub struct MergeOperationInventory(Inventory<InnerMergeOperation>);
 
 impl MergeOperationInventory {
     pub fn segment_in_merge(&self) -> HashSet<SegmentId> {
         let mut segment_in_merge = HashSet::default();
-        for merge_op in self.list() {
+        for merge_op in self.0.list() {
             for &segment_id in &merge_op.segment_ids {
                 segment_in_merge.insert(segment_id);
             }
@@ -44,13 +35,13 @@ pub struct MergeOperation {
     inner: TrackedObject<InnerMergeOperation>,
 }
 
-pub(crate) struct InnerMergeOperation {
+struct InnerMergeOperation {
     target_opstamp: Opstamp,
     segment_ids: Vec<SegmentId>,
 }
 
 impl MergeOperation {
-    pub(crate) fn new(
+    pub fn new(
         inventory: &MergeOperationInventory,
         target_opstamp: Opstamp,
         segment_ids: Vec<SegmentId>,
@@ -60,7 +51,7 @@ impl MergeOperation {
             segment_ids,
         };
         MergeOperation {
-            inner: inventory.track(inner_merge_operation),
+            inner: inventory.0.track(inner_merge_operation),
         }
     }
 

src/indexer/merger.rs

@@ -709,7 +709,7 @@ mod tests {
     use crate::IndexWriter;
     use crate::Searcher;
     use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
-    use futures::executor::block_on;
+    use futures::Future;
     use std::io::Cursor;
 
     #[test]
@@ -792,7 +792,11 @@ mod tests {
                 .searchable_segment_ids()
                 .expect("Searchable segments failed.");
             let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-            block_on(index_writer.merge(&segment_ids)).expect("Merging failed");
+            index_writer
+                .merge(&segment_ids)
+                .expect("Failed to initiate merge")
+                .wait()
+                .expect("Merging failed");
             index_writer.wait_merging_threads().unwrap();
         }
         {
@@ -1036,7 +1040,11 @@ mod tests {
             let segment_ids = index
                 .searchable_segment_ids()
                 .expect("Searchable segments failed.");
-            block_on(index_writer.merge(&segment_ids)).expect("Merging failed");
+            index_writer
+                .merge(&segment_ids)
+                .expect("Failed to initiate merge")
+                .wait()
+                .expect("Merging failed");
             reader.reload().unwrap();
             let searcher = reader.searcher();
             assert_eq!(searcher.segment_readers().len(), 1);
@@ -1131,7 +1139,11 @@ mod tests {
             let segment_ids = index
                 .searchable_segment_ids()
                 .expect("Searchable segments failed.");
-            block_on(index_writer.merge(&segment_ids)).expect("Merging failed");
+            index_writer
+                .merge(&segment_ids)
+                .expect("Failed to initiate merge")
+                .wait()
+                .expect("Merging failed");
             reader.reload().unwrap();
 
             let searcher = reader.searcher();
@@ -1265,7 +1277,11 @@ mod tests {
                 .searchable_segment_ids()
                 .expect("Searchable segments failed.");
             let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-            block_on(index_writer.merge(&segment_ids)).expect("Merging failed");
+            index_writer
+                .merge(&segment_ids)
+                .expect("Failed to initiate merge")
+                .wait()
+                .expect("Merging failed");
             index_writer.wait_merging_threads().unwrap();
             reader.reload().unwrap();
             test_searcher(
@@ -1320,7 +1336,11 @@ mod tests {
         let segment_ids = index
             .searchable_segment_ids()
             .expect("Searchable segments failed.");
-        block_on(index_writer.merge(&segment_ids)).expect("Merging failed");
+        index_writer
+            .merge(&segment_ids)
+            .expect("Failed to initiate merge")
+            .wait()
+            .expect("Merging failed");
         reader.reload().unwrap();
         // commit has not been called yet. The document should still be
         // there.
@@ -1341,18 +1361,22 @@ mod tests {
             let mut doc = Document::default();
             doc.add_u64(int_field, 1);
             index_writer.add_document(doc.clone());
-            assert!(index_writer.commit().is_ok());
+            index_writer.commit().expect("commit failed");
             index_writer.add_document(doc);
-            assert!(index_writer.commit().is_ok());
+            index_writer.commit().expect("commit failed");
             index_writer.delete_term(Term::from_field_u64(int_field, 1));
 
             let segment_ids = index
                 .searchable_segment_ids()
                 .expect("Searchable segments failed.");
-            assert!(block_on(index_writer.merge(&segment_ids)).is_ok());
+            index_writer
+                .merge(&segment_ids)
+                .expect("Failed to initiate merge")
+                .wait()
+                .expect("Merging failed");
 
             // assert delete has not been committed
-            assert!(reader.reload().is_ok());
+            reader.reload().expect("failed to load searcher 1");
             let searcher = reader.searcher();
             assert_eq!(searcher.num_docs(), 2);
 
@@ -1391,12 +1415,12 @@ mod tests {
             index_doc(&mut index_writer, &[1, 5]);
             index_doc(&mut index_writer, &[3]);
             index_doc(&mut index_writer, &[17]);
-            assert!(index_writer.commit().is_ok());
+            index_writer.commit().expect("committed");
             index_doc(&mut index_writer, &[20]);
-            assert!(index_writer.commit().is_ok());
+            index_writer.commit().expect("committed");
             index_doc(&mut index_writer, &[28, 27]);
             index_doc(&mut index_writer, &[1_000]);
-            assert!(index_writer.commit().is_ok());
+            index_writer.commit().expect("committed");
         }
         let reader = index.reader().unwrap();
         let searcher = reader.searcher();
@@ -1428,6 +1452,15 @@ mod tests {
             assert_eq!(&vals, &[17]);
         }
 
+        println!(
+            "{:?}",
+            searcher
+                .segment_readers()
+                .iter()
+                .map(|reader| reader.max_doc())
+                .collect::<Vec<_>>()
+        );
+
         {
             let segment = searcher.segment_reader(1u32);
             let ff_reader = segment.fast_fields().u64s(int_field).unwrap();
@@ -1451,13 +1484,27 @@ mod tests {
                 .searchable_segment_ids()
                 .expect("Searchable segments failed.");
             let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-            assert!(block_on(index_writer.merge(&segment_ids)).is_ok());
-            assert!(index_writer.wait_merging_threads().is_ok());
+            index_writer
+                .merge(&segment_ids)
+                .expect("Failed to initiate merge")
+                .wait()
+                .expect("Merging failed");
+            index_writer
+                .wait_merging_threads()
+                .expect("Wait for merging threads");
         }
-        assert!(reader.reload().is_ok());
+        reader.reload().expect("Load searcher");
 
         {
             let searcher = reader.searcher();
+            println!(
+                "{:?}",
+                searcher
+                    .segment_readers()
+                    .iter()
+                    .map(|reader| reader.max_doc())
+                    .collect::<Vec<_>>()
+            );
             let segment = searcher.segment_reader(0u32);
             let ff_reader = segment.fast_fields().u64s(int_field).unwrap();
 
@@ -1492,46 +1539,4 @@ mod tests {
             assert_eq!(&vals, &[20]);
         }
     }
-
-    #[test]
-    fn merges_f64_fast_fields_correctly() -> crate::Result<()> {
-        let mut builder = schema::SchemaBuilder::new();
-
-        let fast_multi = IntOptions::default().set_fast(Cardinality::MultiValues);
-
-        let field = builder.add_f64_field("f64", schema::FAST);
-        let multi_field = builder.add_f64_field("f64s", fast_multi);
-
-        let index = Index::create_in_ram(builder.build());
-
-        let mut writer = index.writer_with_num_threads(1, 3_000_000)?;
-
-        // Make sure we'll attempt to merge every created segment
-        let mut policy = crate::indexer::LogMergePolicy::default();
-        policy.set_min_merge_size(2);
-        writer.set_merge_policy(Box::new(policy));
-
-        for i in 0..100 {
-            let mut doc = Document::new();
-            doc.add_f64(field, 42.0);
-
-            doc.add_f64(multi_field, 0.24);
-            doc.add_f64(multi_field, 0.27);
-
-            writer.add_document(doc);
-
-            if i % 5 == 0 {
-                writer.commit()?;
-            }
-        }
-
-        writer.commit()?;
-        writer.wait_merging_threads()?;
-
-        // If a merging thread fails, we should end up with more
-        // than one segment here
-        assert_eq!(1, index.searchable_segments()?.len());
-
-        Ok(())
-    }
 }

src/indexer/mod.rs

@@ -18,7 +18,7 @@ mod stamper;
 
 pub use self::index_writer::IndexWriter;
 pub use self::log_merge_policy::LogMergePolicy;
-pub use self::merge_operation::MergeOperation;
+pub use self::merge_operation::{MergeOperation, MergeOperationInventory};
 pub use self::merge_policy::{MergeCandidate, MergePolicy, NoMergePolicy};
 pub use self::prepared_commit::PreparedCommit;
 pub use self::segment_entry::SegmentEntry;
@@ -28,26 +28,3 @@ pub use self::segment_writer::SegmentWriter;
 
 /// Alias for the default merge policy, which is the `LogMergePolicy`.
 pub type DefaultMergePolicy = LogMergePolicy;
-
-#[cfg(test)]
-mod tests {
-    use crate::schema::{self, Schema};
-    use crate::{Index, Term};
-
-    #[test]
-    fn test_advance_delete_bug() {
-        let mut schema_builder = Schema::builder();
-        let text_field = schema_builder.add_text_field("text", schema::TEXT);
-        let index = Index::create_from_tempdir(schema_builder.build()).unwrap();
-        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
-        // there must be one deleted document in the segment
-        index_writer.add_document(doc!(text_field=>"b"));
-        index_writer.delete_term(Term::from_field_text(text_field, "b"));
-        // we need enough data to trigger the bug (at least 32 documents)
-        for _ in 0..32 {
-            index_writer.add_document(doc!(text_field=>"c"));
-        }
-        index_writer.commit().unwrap();
-        index_writer.commit().unwrap();
-    }
-}

src/indexer/prepared_commit.rs

@@ -1,7 +1,6 @@
 use super::IndexWriter;
 use crate::Opstamp;
 use crate::Result;
-use futures::executor::block_on;
 
 /// A prepared commit
 pub struct PreparedCommit<'a> {
@@ -33,11 +32,9 @@ impl<'a> PreparedCommit<'a> {
 
     pub fn commit(self) -> Result<Opstamp> {
         info!("committing {}", self.opstamp);
-        let _ = block_on(
-            self.index_writer
-                .segment_updater()
-                .schedule_commit(self.opstamp, self.payload),
-        );
+        self.index_writer
+            .segment_updater()
+            .commit(self.opstamp, self.payload)?;
         Ok(self.opstamp)
     }
 }

src/indexer/segment_entry.rs

@@ -1,7 +1,7 @@
-use crate::common::BitSet;
 use crate::core::SegmentId;
 use crate::core::SegmentMeta;
 use crate::indexer::delete_queue::DeleteCursor;
+use bit_set::BitSet;
 use std::fmt;
 
 /// A segment entry describes the state of

src/indexer/segment_manager.rs

@@ -16,28 +16,6 @@ struct SegmentRegisters {
     committed: SegmentRegister,
 }
 
-#[derive(PartialEq, Eq)]
-pub(crate) enum SegmentsStatus {
-    Committed,
-    Uncommitted,
-}
-
-impl SegmentRegisters {
-    /// Check if all the segments are committed or uncommited.
-    ///
-    /// If some segment is missing or segments are in a different state (this should not happen
-    /// if tantivy is used correctly), returns `None`.
-    fn segments_status(&self, segment_ids: &[SegmentId]) -> Option<SegmentsStatus> {
-        if self.uncommitted.contains_all(segment_ids) {
-            Some(SegmentsStatus::Uncommitted)
-        } else if self.committed.contains_all(segment_ids) {
-            Some(SegmentsStatus::Committed)
-        } else {
-            None
-        }
-    }
-}
-
 /// The segment manager stores the list of segments
 /// as well as their state.
 ///
@@ -175,35 +153,33 @@ impl SegmentManager {
         let mut registers_lock = self.write();
         registers_lock.uncommitted.add_segment_entry(segment_entry);
     }
-    // Replace a list of segments for their equivalent merged segment.
-    //
-    // Returns true if these segments are committed, false if the merge segments are uncommited.
-    pub(crate) fn end_merge(
+
+    pub fn end_merge(
         &self,
         before_merge_segment_ids: &[SegmentId],
         after_merge_segment_entry: SegmentEntry,
-    ) -> crate::Result<SegmentsStatus> {
+    ) {
         let mut registers_lock = self.write();
-        let segments_status = registers_lock
-            .segments_status(before_merge_segment_ids)
-            .ok_or_else(|| {
+        let target_register: &mut SegmentRegister = {
+            if registers_lock
+                .uncommitted
+                .contains_all(before_merge_segment_ids)
+            {
+                &mut registers_lock.uncommitted
+            } else if registers_lock
+                .committed
+                .contains_all(before_merge_segment_ids)
+            {
+                &mut registers_lock.committed
+            } else {
                 warn!("couldn't find segment in SegmentManager");
-                crate::Error::InvalidArgument(
-                    "The segments that were merged could not be found in the SegmentManager. \
-                     This is not necessarily a bug, and can happen after a rollback for instance."
-                        .to_string(),
-                )
-            })?;
-
-        let target_register: &mut SegmentRegister = match segments_status {
-            SegmentsStatus::Uncommitted => &mut registers_lock.uncommitted,
-            SegmentsStatus::Committed => &mut registers_lock.committed,
+                return;
+            }
         };
         for segment_id in before_merge_segment_ids {
             target_register.remove_segment(segment_id);
         }
         target_register.add_segment_entry(after_merge_segment_entry);
-        Ok(segments_status)
     }
 
     pub fn committed_segment_metas(&self) -> Vec<SegmentMeta> {

src/indexer/segment_serializer.rs

@@ -1,13 +1,10 @@
-use crate::Directory;
+use crate::Result;
 
 use crate::core::Segment;
 use crate::core::SegmentComponent;
-use crate::directory::error::OpenWriteError;
-use crate::directory::{DirectoryClone, RAMDirectory, TerminatingWrite, WritePtr};
 use crate::fastfield::FastFieldSerializer;
 use crate::fieldnorm::FieldNormsSerializer;
 use crate::postings::InvertedIndexSerializer;
-use crate::schema::Schema;
 use crate::store::StoreWriter;
 
 /// Segment serializer is in charge of laying out on disk
@@ -17,50 +14,25 @@ pub struct SegmentSerializer {
     fast_field_serializer: FastFieldSerializer,
     fieldnorms_serializer: FieldNormsSerializer,
     postings_serializer: InvertedIndexSerializer,
-    bundle_writer: Option<(RAMDirectory, WritePtr)>,
-}
-
-pub(crate) struct SegmentSerializerWriters {
-    postings_wrt: WritePtr,
-    positions_skip_wrt: WritePtr,
-    positions_wrt: WritePtr,
-    terms_wrt: WritePtr,
-    fast_field_wrt: WritePtr,
-    fieldnorms_wrt: WritePtr,
-    store_wrt: WritePtr,
-}
-
-impl SegmentSerializerWriters {
-    pub(crate) fn for_segment(segment: &mut Segment) -> Result<Self, OpenWriteError> {
-        Ok(SegmentSerializerWriters {
-            postings_wrt: segment.open_write(SegmentComponent::POSTINGS)?,
-            positions_skip_wrt: segment.open_write(SegmentComponent::POSITIONS)?,
-            positions_wrt: segment.open_write(SegmentComponent::POSITIONSSKIP)?,
-            terms_wrt: segment.open_write(SegmentComponent::TERMS)?,
-            fast_field_wrt: segment.open_write(SegmentComponent::FASTFIELDS)?,
-            fieldnorms_wrt: segment.open_write(SegmentComponent::FIELDNORMS)?,
-            store_wrt: segment.open_write(SegmentComponent::STORE)?,
-        })
-    }
 }
 
 impl SegmentSerializer {
-    pub(crate) fn new(schema: Schema, writers: SegmentSerializerWriters) -> crate::Result<Self> {
-        let fast_field_serializer = FastFieldSerializer::from_write(writers.fast_field_wrt)?;
-        let fieldnorms_serializer = FieldNormsSerializer::from_write(writers.fieldnorms_wrt)?;
-        let postings_serializer = InvertedIndexSerializer::open(
-            schema,
-            writers.terms_wrt,
-            writers.postings_wrt,
-            writers.positions_wrt,
-            writers.positions_skip_wrt,
-        );
+    /// Creates a new `SegmentSerializer`.
+    pub fn for_segment(segment: &mut Segment) -> Result<SegmentSerializer> {
+        let store_write = segment.open_write(SegmentComponent::STORE)?;
+
+        let fast_field_write = segment.open_write(SegmentComponent::FASTFIELDS)?;
+        let fast_field_serializer = FastFieldSerializer::from_write(fast_field_write)?;
+
+        let fieldnorms_write = segment.open_write(SegmentComponent::FIELDNORMS)?;
+        let fieldnorms_serializer = FieldNormsSerializer::from_write(fieldnorms_write)?;
+
+        let postings_serializer = InvertedIndexSerializer::open(segment)?;
         Ok(SegmentSerializer {
-            store_writer: StoreWriter::new(writers.store_wrt),
+            store_writer: StoreWriter::new(store_write),
             fast_field_serializer,
             fieldnorms_serializer,
             postings_serializer,
-            bundle_writer: None,
         })
     }
 
@@ -85,15 +57,11 @@ impl SegmentSerializer {
     }
 
     /// Finalize the segment serialization.
-    pub fn close(mut self) -> crate::Result<()> {
+    pub fn close(self) -> Result<()> {
         self.fast_field_serializer.close()?;
         self.postings_serializer.close()?;
         self.store_writer.close()?;
         self.fieldnorms_serializer.close()?;
-        if let Some((ram_directory, mut bundle_wrt)) = self.bundle_writer.take() {
-            ram_directory.serialize_bundle(&mut bundle_wrt)?;
-            bundle_wrt.terminate()?;
-        }
         Ok(())
     }
 }

src/indexer/segment_updater.rs

@@ -6,35 +6,39 @@ use crate::core::SegmentId;
 use crate::core::SegmentMeta;
 use crate::core::SerializableSegment;
 use crate::core::META_FILEPATH;
-use crate::directory::{Directory, DirectoryClone, GarbageCollectionResult};
+use crate::directory::{Directory, DirectoryClone};
+use crate::error::TantivyError;
 use crate::indexer::delete_queue::DeleteCursor;
 use crate::indexer::index_writer::advance_deletes;
 use crate::indexer::merge_operation::MergeOperationInventory;
 use crate::indexer::merger::IndexMerger;
-use crate::indexer::segment_manager::SegmentsStatus;
-use crate::indexer::segment_serializer::SegmentSerializerWriters;
 use crate::indexer::stamper::Stamper;
+use crate::indexer::MergeOperation;
 use crate::indexer::SegmentEntry;
 use crate::indexer::SegmentSerializer;
 use crate::indexer::{DefaultMergePolicy, MergePolicy};
-use crate::indexer::{MergeCandidate, MergeOperation};
 use crate::schema::Schema;
 use crate::Opstamp;
-use futures::channel::oneshot;
-use futures::executor::{ThreadPool, ThreadPoolBuilder};
-use futures::future::Future;
-use futures::future::TryFutureExt;
+use crate::Result;
+use futures::oneshot;
+use futures::sync::oneshot::Receiver;
+use futures::Future;
+use futures_cpupool::Builder as CpuPoolBuilder;
+use futures_cpupool::CpuFuture;
+use futures_cpupool::CpuPool;
 use serde_json;
 use std::borrow::BorrowMut;
+use std::collections::HashMap;
 use std::collections::HashSet;
 use std::io::Write;
-use std::ops::Deref;
+use std::mem;
+use std::ops::DerefMut;
 use std::path::PathBuf;
-use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
 use std::sync::Arc;
 use std::sync::RwLock;
-
-const NUM_MERGE_THREADS: usize = 4;
+use std::thread;
+use std::thread::JoinHandle;
 
 /// Save the index meta file.
 /// This operation is atomic :
@@ -45,7 +49,7 @@ const NUM_MERGE_THREADS: usize = 4;
 /// and flushed.
 ///
 /// This method is not part of tantivy's public API
-pub fn save_new_metas(schema: Schema, directory: &mut dyn Directory) -> crate::Result<()> {
+pub fn save_new_metas(schema: Schema, directory: &mut dyn Directory) -> Result<()> {
     save_metas(
         &IndexMeta {
             segments: Vec::new(),
@@ -66,7 +70,7 @@ pub fn save_new_metas(schema: Schema, directory: &mut dyn Directory) -> crate::R
 /// and flushed.
 ///
 /// This method is not part of tantivy's public API
-fn save_metas(metas: &IndexMeta, directory: &mut dyn Directory) -> crate::Result<()> {
+fn save_metas(metas: &IndexMeta, directory: &mut dyn Directory) -> Result<()> {
     info!("save metas");
     let mut buffer = serde_json::to_vec_pretty(metas)?;
     // Just adding a new line at the end of the buffer.
@@ -85,38 +89,21 @@ fn save_metas(metas: &IndexMeta, directory: &mut dyn Directory) -> crate::Result
 // We voluntarily pass a merge_operation ref to guarantee that
 // the merge_operation is alive during the process
 #[derive(Clone)]
-pub(crate) struct SegmentUpdater(Arc<InnerSegmentUpdater>);
+pub struct SegmentUpdater(Arc<InnerSegmentUpdater>);
 
-impl Deref for SegmentUpdater {
-    type Target = InnerSegmentUpdater;
-
-    #[inline]
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
-
-async fn garbage_collect_files(
-    segment_updater: SegmentUpdater,
-) -> crate::Result<GarbageCollectionResult> {
-    info!("Running garbage collection");
-    let mut index = segment_updater.index.clone();
-    index
-        .directory_mut()
-        .garbage_collect(move || segment_updater.list_files())
-}
-
-/// Merges a list of segments the list of segment givens in the `segment_entries`.
-/// This function happens in the calling thread and is computationally expensive.
-fn merge(
+fn perform_merge(
+    merge_operation: &MergeOperation,
     index: &Index,
     mut segment_entries: Vec<SegmentEntry>,
-    target_opstamp: Opstamp,
-) -> crate::Result<SegmentEntry> {
+) -> Result<SegmentEntry> {
+    let target_opstamp = merge_operation.target_opstamp();
+
     // first we need to apply deletes to our segment.
     let mut merged_segment = index.new_segment();
 
-    // First we apply all of the delet to the merged segment, up to the target opstamp.
+    // TODO add logging
+    let schema = index.schema();
+
     for segment_entry in &mut segment_entries {
         let segment = index.segment(segment_entry.meta().clone());
         advance_deletes(segment, segment_entry, target_opstamp)?;
@@ -130,21 +117,22 @@ fn merge(
         .collect();
 
     // An IndexMerger is like a "view" of our merged segments.
-    let merger: IndexMerger = IndexMerger::open(index.schema(), &segments[..])?;
+    let merger: IndexMerger = IndexMerger::open(schema, &segments[..])?;
 
-    // ... we just serialize this index merger in our new segment to merge the two segments.
-    let segment_serializer_wrts = SegmentSerializerWriters::for_segment(&mut merged_segment)?;
-    let segment_serializer =
-        SegmentSerializer::new(merged_segment.schema(), segment_serializer_wrts)?;
+    // ... we just serialize this index merger in our new segment
+    // to merge the two segments.
+
+    let segment_serializer = SegmentSerializer::for_segment(&mut merged_segment)?;
 
     let num_docs = merger.write(segment_serializer)?;
 
     let segment_meta = index.new_segment_meta(merged_segment.id(), num_docs);
 
-    Ok(SegmentEntry::new(segment_meta, delete_cursor, None))
+    let after_merge_segment_entry = SegmentEntry::new(segment_meta.clone(), delete_cursor, None);
+    Ok(after_merge_segment_entry)
 }
 
-pub(crate) struct InnerSegmentUpdater {
+struct InnerSegmentUpdater {
     // we keep a copy of the current active IndexMeta to
     // avoid loading the file everytime we need it in the
     // `SegmentUpdater`.
@@ -152,12 +140,12 @@ pub(crate) struct InnerSegmentUpdater {
     // This should be up to date as all update happen through
     // the unique active `SegmentUpdater`.
     active_metas: RwLock<Arc<IndexMeta>>,
-    pool: ThreadPool,
-    merge_thread_pool: ThreadPool,
-
+    pool: CpuPool,
     index: Index,
     segment_manager: SegmentManager,
     merge_policy: RwLock<Arc<Box<dyn MergePolicy>>>,
+    merging_thread_id: AtomicUsize,
+    merging_threads: RwLock<HashMap<usize, JoinHandle<Result<()>>>>,
     killed: AtomicBool,
     stamper: Stamper,
     merge_operations: MergeOperationInventory,
@@ -168,31 +156,22 @@ impl SegmentUpdater {
         index: Index,
         stamper: Stamper,
         delete_cursor: &DeleteCursor,
-    ) -> crate::Result<SegmentUpdater> {
+    ) -> Result<SegmentUpdater> {
         let segments = index.searchable_segment_metas()?;
         let segment_manager = SegmentManager::from_segments(segments, delete_cursor);
-        let pool = ThreadPoolBuilder::new()
+        let pool = CpuPoolBuilder::new()
             .name_prefix("segment_updater")
             .pool_size(1)
-            .create()
-            .map_err(|_| {
-                crate::Error::SystemError("Failed to spawn segment updater thread".to_string())
-            })?;
-        let merge_thread_pool = ThreadPoolBuilder::new()
-            .name_prefix("merge_thread")
-            .pool_size(NUM_MERGE_THREADS)
-            .create()
-            .map_err(|_| {
-                crate::Error::SystemError("Failed to spawn segment merging thread".to_string())
-            })?;
+            .create();
         let index_meta = index.load_metas()?;
         Ok(SegmentUpdater(Arc::new(InnerSegmentUpdater {
             active_metas: RwLock::new(Arc::new(index_meta)),
             pool,
-            merge_thread_pool,
             index,
             segment_manager,
             merge_policy: RwLock::new(Arc::new(Box::new(DefaultMergePolicy::default()))),
+            merging_thread_id: AtomicUsize::default(),
+            merging_threads: RwLock::new(HashMap::new()),
             killed: AtomicBool::new(false),
             stamper,
             merge_operations: Default::default(),
@@ -200,82 +179,67 @@ impl SegmentUpdater {
     }
 
     pub fn get_merge_policy(&self) -> Arc<Box<dyn MergePolicy>> {
-        self.merge_policy.read().unwrap().clone()
+        self.0.merge_policy.read().unwrap().clone()
     }
 
     pub fn set_merge_policy(&self, merge_policy: Box<dyn MergePolicy>) {
         let arc_merge_policy = Arc::new(merge_policy);
-        *self.merge_policy.write().unwrap() = arc_merge_policy;
+        *self.0.merge_policy.write().unwrap() = arc_merge_policy;
     }
 
-    fn schedule_future<T: 'static + Send, F: Future<Output = crate::Result<T>> + 'static + Send>(
+    fn get_merging_thread_id(&self) -> usize {
+        self.0.merging_thread_id.fetch_add(1, Ordering::SeqCst)
+    }
+
+    fn run_async<T: 'static + Send, F: 'static + Send + FnOnce(SegmentUpdater) -> T>(
         &self,
         f: F,
-    ) -> impl Future<Output = crate::Result<T>> {
-        let (sender, receiver) = oneshot::channel();
-        if self.is_alive() {
-            self.pool.spawn_ok(async move {
-                let _ = sender.send(f.await);
-            });
-        } else {
-            let _ = sender.send(Err(crate::TantivyError::SystemError(
-                "Segment updater killed".to_string(),
-            )));
-        }
-        receiver.unwrap_or_else(|_| {
-            let err_msg =
-                "A segment_updater future did not success. This should never happen.".to_string();
-            Err(crate::Error::SystemError(err_msg))
-        })
+    ) -> CpuFuture<T, TantivyError> {
+        let me_clone = self.clone();
+        self.0.pool.spawn_fn(move || Ok(f(me_clone)))
     }
 
-    pub fn schedule_add_segment(
-        &self,
-        segment_entry: SegmentEntry,
-    ) -> impl Future<Output = crate::Result<()>> {
-        let segment_updater = self.clone();
-        self.schedule_future(async move {
-            segment_updater.segment_manager.add_segment(segment_entry);
-            segment_updater.consider_merge_options().await;
-            Ok(())
+    pub fn add_segment(&self, segment_entry: SegmentEntry) -> bool {
+        self.run_async(|segment_updater| {
+            segment_updater.0.segment_manager.add_segment(segment_entry);
+            segment_updater.consider_merge_options();
+            true
         })
+        .forget();
+        true
     }
 
     /// Orders `SegmentManager` to remove all segments
     pub(crate) fn remove_all_segments(&self) {
-        self.segment_manager.remove_all_segments();
+        self.0.segment_manager.remove_all_segments();
     }
 
     pub fn kill(&mut self) {
-        self.killed.store(true, Ordering::Release);
+        self.0.killed.store(true, Ordering::Release);
     }
 
     pub fn is_alive(&self) -> bool {
-        !self.killed.load(Ordering::Acquire)
+        !self.0.killed.load(Ordering::Acquire)
     }
 
     /// Apply deletes up to the target opstamp to all segments.
     ///
     /// The method returns copies of the segment entries,
     /// updated with the delete information.
-    fn purge_deletes(&self, target_opstamp: Opstamp) -> crate::Result<Vec<SegmentEntry>> {
-        let mut segment_entries = self.segment_manager.segment_entries();
+    fn purge_deletes(&self, target_opstamp: Opstamp) -> Result<Vec<SegmentEntry>> {
+        let mut segment_entries = self.0.segment_manager.segment_entries();
         for segment_entry in &mut segment_entries {
-            let segment = self.index.segment(segment_entry.meta().clone());
+            let segment = self.0.index.segment(segment_entry.meta().clone());
             advance_deletes(segment, segment_entry, target_opstamp)?;
         }
         Ok(segment_entries)
     }
 
-    pub fn save_metas(
-        &self,
-        opstamp: Opstamp,
-        commit_message: Option<String>,
-    ) -> crate::Result<()> {
+    pub fn save_metas(&self, opstamp: Opstamp, commit_message: Option<String>) {
         if self.is_alive() {
-            let index = &self.index;
+            let index = &self.0.index;
             let directory = index.directory();
-            let mut commited_segment_metas = self.segment_manager.committed_segment_metas();
+            let mut commited_segment_metas = self.0.segment_manager.committed_segment_metas();
 
             // We sort segment_readers by number of documents.
             // This is an heuristic to make multithreading more efficient.
@@ -297,18 +261,16 @@ impl SegmentUpdater {
                 opstamp,
                 payload: commit_message,
             };
-            // TODO add context to the error.
-            save_metas(&index_meta, directory.box_clone().borrow_mut())?;
+            save_metas(&index_meta, directory.box_clone().borrow_mut())
+                .expect("Could not save metas.");
             self.store_meta(&index_meta);
         }
-        Ok(())
     }
 
-    pub fn schedule_garbage_collect(
-        &self,
-    ) -> impl Future<Output = crate::Result<GarbageCollectionResult>> {
-        let garbage_collect_future = garbage_collect_files(self.clone());
-        self.schedule_future(garbage_collect_future)
+    pub fn garbage_collect_files(&self) -> CpuFuture<(), TantivyError> {
+        self.run_async(move |segment_updater| {
+            segment_updater.garbage_collect_files_exec();
+        })
     }
 
     /// List the files that are useful to the index.
@@ -316,130 +278,148 @@ impl SegmentUpdater {
     /// This does not include lock files, or files that are obsolete
     /// but have not yet been deleted by the garbage collector.
     fn list_files(&self) -> HashSet<PathBuf> {
-        let mut files: HashSet<PathBuf> = self
-            .index
-            .list_all_segment_metas()
-            .into_iter()
-            .flat_map(|segment_meta| segment_meta.list_files())
-            .collect();
+        let mut files = HashSet::new();
         files.insert(META_FILEPATH.to_path_buf());
+        for segment_meta in self.0.index.list_all_segment_metas() {
+            files.extend(segment_meta.list_files());
+        }
         files
     }
 
-    pub fn schedule_commit(
-        &self,
-        opstamp: Opstamp,
-        payload: Option<String>,
-    ) -> impl Future<Output = crate::Result<()>> {
-        let segment_updater: SegmentUpdater = self.clone();
-        self.schedule_future(async move {
-            let segment_entries = segment_updater.purge_deletes(opstamp)?;
-            segment_updater.segment_manager.commit(segment_entries);
-            segment_updater.save_metas(opstamp, payload)?;
-            let _ = garbage_collect_files(segment_updater.clone()).await;
-            segment_updater.consider_merge_options().await;
-            Ok(())
+    fn garbage_collect_files_exec(&self) {
+        info!("Running garbage collection");
+        let mut index = self.0.index.clone();
+        index.directory_mut().garbage_collect(|| self.list_files());
+    }
+
+    pub fn commit(&self, opstamp: Opstamp, payload: Option<String>) -> Result<()> {
+        self.run_async(move |segment_updater| {
+            if segment_updater.is_alive() {
+                let segment_entries = segment_updater
+                    .purge_deletes(opstamp)
+                    .expect("Failed purge deletes");
+                segment_updater.0.segment_manager.commit(segment_entries);
+                segment_updater.save_metas(opstamp, payload);
+                segment_updater.garbage_collect_files_exec();
+                segment_updater.consider_merge_options();
+            }
         })
+        .wait()
+    }
+
+    pub fn start_merge(&self, segment_ids: &[SegmentId]) -> Result<Receiver<SegmentMeta>> {
+        let commit_opstamp = self.load_metas().opstamp;
+        let merge_operation = MergeOperation::new(
+            &self.0.merge_operations,
+            commit_opstamp,
+            segment_ids.to_vec(),
+        );
+        self.run_async(move |segment_updater| segment_updater.start_merge_impl(merge_operation))
+            .wait()?
     }
 
     fn store_meta(&self, index_meta: &IndexMeta) {
-        *self.active_metas.write().unwrap() = Arc::new(index_meta.clone());
+        *self.0.active_metas.write().unwrap() = Arc::new(index_meta.clone());
     }
-
     fn load_metas(&self) -> Arc<IndexMeta> {
-        self.active_metas.read().unwrap().clone()
+        self.0.active_metas.read().unwrap().clone()
     }
 
-    pub(crate) fn make_merge_operation(&self, segment_ids: &[SegmentId]) -> MergeOperation {
-        let commit_opstamp = self.load_metas().opstamp;
-        MergeOperation::new(&self.merge_operations, commit_opstamp, segment_ids.to_vec())
-    }
-
-    // Starts a merge operation. This function will block until the merge operation is effectively
-    // started. Note that it does not wait for the merge to terminate.
-    // The calling thread should not be block for a long time, as this only involve waiting for the
-    // `SegmentUpdater` queue which in turns only contains lightweight operations.
-    //
-    // The merge itself happens on a different thread.
-    //
-    // When successful, this function returns a `Future` for a `Result<SegmentMeta>` that represents
-    // the actual outcome of the merge operation.
-    //
-    // It returns an error if for some reason the merge operation could not be started.
-    //
-    // At this point an error is not necessarily the sign of a malfunction.
-    // (e.g. A rollback could have happened, between the instant when the merge operaiton was
-    // suggested and the moment when it ended up being executed.)
-    //
     // `segment_ids` is required to be non-empty.
-    pub fn start_merge(
-        &self,
-        merge_operation: MergeOperation,
-    ) -> crate::Result<impl Future<Output = crate::Result<SegmentMeta>>> {
+    fn start_merge_impl(&self, merge_operation: MergeOperation) -> Result<Receiver<SegmentMeta>> {
         assert!(
             !merge_operation.segment_ids().is_empty(),
             "Segment_ids cannot be empty."
         );
 
-        let segment_updater = self.clone();
+        let segment_updater_clone = self.clone();
         let segment_entries: Vec<SegmentEntry> = self
+            .0
             .segment_manager
             .start_merge(merge_operation.segment_ids())?;
 
-        info!("Starting merge  - {:?}", merge_operation.segment_ids());
+        //        let segment_ids_vec = merge_operation.segment_ids.to_vec();
 
-        let (merging_future_send, merging_future_recv) =
-            oneshot::channel::<crate::Result<SegmentMeta>>();
+        let merging_thread_id = self.get_merging_thread_id();
+        info!(
+            "Starting merge thread #{} - {:?}",
+            merging_thread_id,
+            merge_operation.segment_ids()
+        );
+        let (merging_future_send, merging_future_recv) = oneshot();
 
-        self.merge_thread_pool.spawn_ok(async move {
-            // The fact that `merge_operation` is moved here is important.
-            // Its lifetime is used to track how many merging thread are currently running,
-            // as well as which segment is currently in merge and therefore should not be
-            // candidate for another merge.
-            match merge(
-                &segment_updater.index,
-                segment_entries,
-                merge_operation.target_opstamp(),
-            ) {
-                Ok(after_merge_segment_entry) => {
-                    let segment_meta = segment_updater
-                        .end_merge(merge_operation, after_merge_segment_entry)
-                        .await;
-                    let _send_result = merging_future_send.send(segment_meta);
-                }
-                Err(e) => {
-                    warn!(
-                        "Merge of {:?} was cancelled: {:?}",
-                        merge_operation.segment_ids().to_vec(),
-                        e
-                    );
-                    // ... cancel merge
-                    if cfg!(test) {
-                        panic!("Merge failed.");
+        // first we need to apply deletes to our segment.
+        let merging_join_handle = thread::Builder::new()
+            .name(format!("mergingthread-{}", merging_thread_id))
+            .spawn(move || {
+                // first we need to apply deletes to our segment.
+                let merge_result = perform_merge(
+                    &merge_operation,
+                    &segment_updater_clone.0.index,
+                    segment_entries,
+                );
+
+                match merge_result {
+                    Ok(after_merge_segment_entry) => {
+                        let merged_segment_meta = after_merge_segment_entry.meta().clone();
+                        segment_updater_clone
+                            .end_merge(merge_operation, after_merge_segment_entry)
+                            .expect("Segment updater thread is corrupted.");
+
+                        // the future may fail if the listener of the oneshot future
+                        // has been destroyed.
+                        //
+                        // This is not a problem here, so we just ignore any
+                        // possible error.
+                        let _merging_future_res = merging_future_send.send(merged_segment_meta);
+                    }
+                    Err(e) => {
+                        warn!(
+                            "Merge of {:?} was cancelled: {:?}",
+                            merge_operation.segment_ids(),
+                            e
+                        );
+                        // ... cancel merge
+                        if cfg!(test) {
+                            panic!("Merge failed.");
+                        }
+                        // As `merge_operation` will be dropped, the segment in merge state will
+                        // be available for merge again.
+                        // `merging_future_send` will be dropped, sending an error to the future.
                     }
                 }
-            }
-        });
-
-        Ok(merging_future_recv
-            .unwrap_or_else(|_| Err(crate::Error::SystemError("Merge failed".to_string()))))
+                segment_updater_clone
+                    .0
+                    .merging_threads
+                    .write()
+                    .unwrap()
+                    .remove(&merging_thread_id);
+                Ok(())
+            })
+            .expect("Failed to spawn a thread.");
+        self.0
+            .merging_threads
+            .write()
+            .unwrap()
+            .insert(merging_thread_id, merging_join_handle);
+        Ok(merging_future_recv)
     }
 
-    async fn consider_merge_options(&self) {
-        let merge_segment_ids: HashSet<SegmentId> = self.merge_operations.segment_in_merge();
+    fn consider_merge_options(&self) {
+        let merge_segment_ids: HashSet<SegmentId> = self.0.merge_operations.segment_in_merge();
         let (committed_segments, uncommitted_segments) =
-            get_mergeable_segments(&merge_segment_ids, &self.segment_manager);
+            get_mergeable_segments(&merge_segment_ids, &self.0.segment_manager);
 
         // Committed segments cannot be merged with uncommitted_segments.
         // We therefore consider merges using these two sets of segments independently.
         let merge_policy = self.get_merge_policy();
 
-        let current_opstamp = self.stamper.stamp();
+        let current_opstamp = self.0.stamper.stamp();
         let mut merge_candidates: Vec<MergeOperation> = merge_policy
             .compute_merge_candidates(&uncommitted_segments)
             .into_iter()
             .map(|merge_candidate| {
-                MergeOperation::new(&self.merge_operations, current_opstamp, merge_candidate.0)
+                MergeOperation::new(&self.0.merge_operations, current_opstamp, merge_candidate.0)
             })
             .collect();
 
@@ -447,18 +427,25 @@ impl SegmentUpdater {
         let committed_merge_candidates = merge_policy
             .compute_merge_candidates(&committed_segments)
             .into_iter()
-            .map(|merge_candidate: MergeCandidate| {
-                MergeOperation::new(&self.merge_operations, commit_opstamp, merge_candidate.0)
+            .map(|merge_candidate| {
+                MergeOperation::new(&self.0.merge_operations, commit_opstamp, merge_candidate.0)
             })
             .collect::<Vec<_>>();
         merge_candidates.extend(committed_merge_candidates.into_iter());
 
         for merge_operation in merge_candidates {
-            if let Err(err) = self.start_merge(merge_operation) {
-                warn!(
-                    "Starting the merge failed for the following reason. This is not fatal. {}",
-                    err
-                );
+            match self.start_merge_impl(merge_operation) {
+                Ok(merge_future) => {
+                    if let Err(e) = merge_future.fuse().poll() {
+                        error!("The merge task failed quickly after starting: {:?}", e);
+                    }
+                }
+                Err(err) => {
+                    warn!(
+                        "Starting the merge failed for the following reason. This is not fatal. {}",
+                        err
+                    );
+                }
             }
         }
     }
@@ -467,17 +454,15 @@ impl SegmentUpdater {
         &self,
         merge_operation: MergeOperation,
         mut after_merge_segment_entry: SegmentEntry,
-    ) -> impl Future<Output = crate::Result<SegmentMeta>> {
-        let segment_updater = self.clone();
-        let after_merge_segment_meta = after_merge_segment_entry.meta().clone();
-        let end_merge_future = self.schedule_future(async move {
+    ) -> Result<()> {
+        self.run_async(move |segment_updater| {
             info!("End merge {:?}", after_merge_segment_entry.meta());
             {
                 let mut delete_cursor = after_merge_segment_entry.delete_cursor().clone();
                 if let Some(delete_operation) = delete_cursor.get() {
                     let committed_opstamp = segment_updater.load_metas().opstamp;
                     if delete_operation.opstamp < committed_opstamp {
-                        let index = &segment_updater.index;
+                        let index = &segment_updater.0.index;
                         let segment = index.segment(after_merge_segment_entry.meta().clone());
                         if let Err(e) = advance_deletes(
                             segment,
@@ -495,26 +480,21 @@ impl SegmentUpdater {
                             // ... cancel merge
                             // `merge_operations` are tracked. As it is dropped, the
                             // the segment_ids will be available again for merge.
-                            return Err(e);
+                            return;
                         }
                     }
                 }
                 let previous_metas = segment_updater.load_metas();
-                let segments_status = segment_updater
+                segment_updater
+                    .0
                     .segment_manager
-                    .end_merge(merge_operation.segment_ids(), after_merge_segment_entry)?;
-
-                if segments_status == SegmentsStatus::Committed {
-                    segment_updater
-                        .save_metas(previous_metas.opstamp, previous_metas.payload.clone())?;
-                }
-
-                segment_updater.consider_merge_options().await;
+                    .end_merge(merge_operation.segment_ids(), after_merge_segment_entry);
+                segment_updater.consider_merge_options();
+                segment_updater.save_metas(previous_metas.opstamp, previous_metas.payload.clone());
             } // we drop all possible handle to a now useless `SegmentMeta`.
-            let _ = garbage_collect_files(segment_updater).await;
-            Ok(())
-        });
-        end_merge_future.map_ok(|_| after_merge_segment_meta)
+            segment_updater.garbage_collect_files_exec();
+        })
+        .wait()
     }
 
     /// Wait for current merging threads.
@@ -532,9 +512,26 @@ impl SegmentUpdater {
     ///
     /// Obsolete files will eventually be cleaned up
     /// by the directory garbage collector.
-    pub fn wait_merging_thread(&self) -> crate::Result<()> {
-        self.merge_operations.wait_until_empty();
-        Ok(())
+    pub fn wait_merging_thread(&self) -> Result<()> {
+        loop {
+            let merging_threads: HashMap<usize, JoinHandle<Result<()>>> = {
+                let mut merging_threads = self.0.merging_threads.write().unwrap();
+                mem::replace(merging_threads.deref_mut(), HashMap::new())
+            };
+            if merging_threads.is_empty() {
+                return Ok(());
+            }
+            debug!("wait merging thread {}", merging_threads.len());
+            for (_, merging_thread_handle) in merging_threads {
+                merging_thread_handle
+                    .join()
+                    .map(|_| ())
+                    .map_err(|_| TantivyError::ErrorInThread("Merging thread failed.".into()))?;
+            }
+            // Our merging thread may have queued their completed merged segment.
+            // Let's wait for that too.
+            self.run_async(move |_| {}).wait()?;
+        }
     }
 }
 
@@ -690,6 +687,7 @@ mod tests {
         index_writer.segment_updater().remove_all_segments();
         let seg_vec = index_writer
             .segment_updater()
+            .0
             .segment_manager
             .segment_entries();
         assert!(seg_vec.is_empty());

src/indexer/segment_writer.rs

@@ -3,7 +3,7 @@ use crate::core::Segment;
 use crate::core::SerializableSegment;
 use crate::fastfield::FastFieldsWriter;
 use crate::fieldnorm::FieldNormsWriter;
-use crate::indexer::segment_serializer::{SegmentSerializer, SegmentSerializerWriters};
+use crate::indexer::segment_serializer::SegmentSerializer;
 use crate::postings::compute_table_size;
 use crate::postings::MultiFieldPostingsWriter;
 use crate::schema::FieldType;
@@ -13,8 +13,7 @@ use crate::schema::Value;
 use crate::schema::{Field, FieldEntry};
 use crate::tokenizer::BoxedTokenizer;
 use crate::tokenizer::FacetTokenizer;
-use crate::tokenizer::PreTokenizedStream;
-use crate::tokenizer::{TokenStream, TokenStreamChain, Tokenizer};
+use crate::tokenizer::{TokenStream, Tokenizer};
 use crate::DocId;
 use crate::Opstamp;
 use crate::Result;
@@ -69,8 +68,7 @@ impl SegmentWriter {
         schema: &Schema,
     ) -> Result<SegmentWriter> {
         let table_num_bits = initial_table_size(memory_budget)?;
-        let segment_serializer_wrts = SegmentSerializerWriters::for_segment(&mut segment)?;
-        let segment_serializer = SegmentSerializer::new(segment.schema(), segment_serializer_wrts)?;
+        let segment_serializer = SegmentSerializer::for_segment(&mut segment)?;
         let multifield_postings = MultiFieldPostingsWriter::new(schema, table_num_bits);
         let tokenizers = schema
             .fields()
@@ -160,44 +158,26 @@ impl SegmentWriter {
                     }
                 }
                 FieldType::Str(_) => {
-                    let mut token_streams: Vec<Box<dyn TokenStream>> = vec![];
-                    let mut offsets = vec![];
-                    let mut total_offset = 0;
-
-                    for field_value in field_values {
-                        match field_value.value() {
-                            Value::PreTokStr(tok_str) => {
-                                offsets.push(total_offset);
-                                if let Some(last_token) = tok_str.tokens.last() {
-                                    total_offset += last_token.offset_to;
-                                }
-
-                                token_streams
-                                    .push(Box::new(PreTokenizedStream::from(tok_str.clone())));
-                            }
-                            Value::Str(ref text) => {
-                                if let Some(ref mut tokenizer) =
-                                    self.tokenizers[field.field_id() as usize]
-                                {
-                                    offsets.push(total_offset);
-                                    total_offset += text.len();
-
-                                    token_streams.push(tokenizer.token_stream(text));
-                                }
-                            }
-                            _ => (),
+                    let num_tokens = if let Some(ref mut tokenizer) =
+                        self.tokenizers[field.field_id() as usize]
+                    {
+                        let texts: Vec<&str> = field_values
+                            .iter()
+                            .flat_map(|field_value| match *field_value.value() {
+                                Value::Str(ref text) => Some(text.as_str()),
+                                _ => None,
+                            })
+                            .collect();
+                        if texts.is_empty() {
+                            0
+                        } else {
+                            let mut token_stream = tokenizer.token_stream_texts(&texts[..]);
+                            self.multifield_postings
+                                .index_text(doc_id, field, &mut token_stream)
                         }
-                    }
-
-                    let num_tokens = if token_streams.is_empty() {
-                        0
                     } else {
-                        let mut token_stream: Box<dyn TokenStream> =
-                            Box::new(TokenStreamChain::new(offsets, token_streams));
-                        self.multifield_postings
-                            .index_text(doc_id, field, &mut token_stream)
+                        0
                     };
-
                     self.fieldnorms_writer.record(doc_id, field, num_tokens);
                 }
                 FieldType::U64(ref int_option) => {
@@ -250,7 +230,6 @@ impl SegmentWriter {
             }
         }
         doc.filter_fields(|field| schema.get_field_entry(field).is_stored());
-        doc.prepare_for_store();
         let doc_writer = self.segment_serializer.get_store_writer();
         doc_writer.store(&doc)?;
         self.max_doc += 1;

src/lib.rs

@@ -160,6 +160,7 @@ pub use self::snippet::{Snippet, SnippetGenerator};
 
 mod docset;
 pub use self::docset::{DocSet, SkipResult};
+
 pub use crate::common::{f64_to_u64, i64_to_u64, u64_to_f64, u64_to_i64};
 pub use crate::core::SegmentComponent;
 pub use crate::core::{Index, IndexMeta, Searcher, Segment, SegmentId, SegmentMeta};
@@ -169,58 +170,11 @@ pub use crate::indexer::IndexWriter;
 pub use crate::postings::Postings;
 pub use crate::reader::LeasedItem;
 pub use crate::schema::{Document, Term};
-use std::fmt;
 
-use once_cell::sync::Lazy;
-
-/// Index format version.
-const INDEX_FORMAT_VERSION: u32 = 1;
-
-/// Structure version for the index.
-#[derive(Clone, PartialEq, Eq, Serialize, Deserialize)]
-pub struct Version {
-    major: u32,
-    minor: u32,
-    patch: u32,
-    index_format_version: u32,
-    store_compression: String,
-}
-
-impl fmt::Debug for Version {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "{}", self.to_string())
-    }
-}
-
-static VERSION: Lazy<Version> = Lazy::new(|| Version {
-    major: env!("CARGO_PKG_VERSION_MAJOR").parse().unwrap(),
-    minor: env!("CARGO_PKG_VERSION_MINOR").parse().unwrap(),
-    patch: env!("CARGO_PKG_VERSION_PATCH").parse().unwrap(),
-    index_format_version: INDEX_FORMAT_VERSION,
-    store_compression: crate::store::COMPRESSION.to_string(),
-});
-
-impl ToString for Version {
-    fn to_string(&self) -> String {
-        format!(
-            "tantivy v{}.{}.{}, index_format v{}, store_compression: {}",
-            self.major, self.minor, self.patch, self.index_format_version, self.store_compression
-        )
-    }
-}
-
-static VERSION_STRING: Lazy<String> = Lazy::new(|| VERSION.to_string());
-
-/// Expose the current version of tantivy as found in Cargo.toml during compilation.
-/// eg. "0.11.0" as well as the compression scheme used in the docstore.
-pub fn version() -> &'static Version {
-    &VERSION
-}
-
-/// Exposes the complete version of tantivy as found in Cargo.toml during compilation as a string.
-/// eg. "tantivy v0.11.0, index_format v1, store_compression: lz4".
-pub fn version_string() -> &'static str {
-    VERSION_STRING.as_str()
+/// Expose the current version of tantivy, as well
+/// whether it was compiled with the simd compression.
+pub fn version() -> &'static str {
+    env!("CARGO_PKG_VERSION")
 }
 
 /// Defines tantivy's merging strategy
@@ -333,18 +287,6 @@ mod tests {
         sample_with_seed(n, ratio, 4)
     }
 
-    #[test]
-    #[cfg(not(feature = "lz4"))]
-    fn test_version_string() {
-        use regex::Regex;
-        let regex_ptn = Regex::new(
-            "tantivy v[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.{0,10}, index_format v[0-9]{1,5}",
-        )
-        .unwrap();
-        let version = super::version().to_string();
-        assert!(regex_ptn.find(&version).is_some());
-    }
-
     #[test]
     #[cfg(feature = "mmap")]
     fn test_indexing() {
@@ -940,73 +882,4 @@ mod tests {
             assert_eq!(fast_field_reader.get(0), 4f64)
         }
     }
-
-    // motivated by #729
-    #[test]
-    fn test_update_via_delete_insert() {
-        use crate::collector::Count;
-        use crate::indexer::NoMergePolicy;
-        use crate::query::AllQuery;
-        use crate::SegmentId;
-        use futures::executor::block_on;
-
-        const DOC_COUNT: u64 = 2u64;
-
-        let mut schema_builder = SchemaBuilder::default();
-        let id = schema_builder.add_u64_field("id", INDEXED);
-        let schema = schema_builder.build();
-
-        let index = Index::create_in_ram(schema.clone());
-        let index_reader = index.reader().unwrap();
-
-        let mut index_writer = index.writer(3_000_000).unwrap();
-        index_writer.set_merge_policy(Box::new(NoMergePolicy));
-
-        for doc_id in 0u64..DOC_COUNT {
-            index_writer.add_document(doc!(id => doc_id));
-        }
-        index_writer.commit().unwrap();
-
-        index_reader.reload().unwrap();
-        let searcher = index_reader.searcher();
-
-        assert_eq!(
-            searcher.search(&AllQuery, &Count).unwrap(),
-            DOC_COUNT as usize
-        );
-
-        // update the 10 elements by deleting and re-adding
-        for doc_id in 0u64..DOC_COUNT {
-            index_writer.delete_term(Term::from_field_u64(id, doc_id));
-            index_writer.commit().unwrap();
-            index_reader.reload().unwrap();
-            let doc = doc!(id =>  doc_id);
-            index_writer.add_document(doc);
-            index_writer.commit().unwrap();
-            index_reader.reload().unwrap();
-            let searcher = index_reader.searcher();
-            // The number of document should be stable.
-            assert_eq!(
-                searcher.search(&AllQuery, &Count).unwrap(),
-                DOC_COUNT as usize
-            );
-        }
-
-        index_reader.reload().unwrap();
-        let searcher = index_reader.searcher();
-        let segment_ids: Vec<SegmentId> = searcher
-            .segment_readers()
-            .into_iter()
-            .map(|reader| reader.segment_id())
-            .collect();
-        block_on(index_writer.merge(&segment_ids)).unwrap();
-
-        index_reader.reload().unwrap();
-        let searcher = index_reader.searcher();
-
-        assert_eq!(
-            searcher.search(&AllQuery, &Count).unwrap(),
-            DOC_COUNT as usize
-        );
-    }
 }

src/macros.rs

@@ -35,9 +35,9 @@
 /// let likes = schema_builder.add_u64_field("num_u64", FAST);
 /// let schema = schema_builder.build();
 /// let doc = doc!(
-///     title => "Life Aquatic",
-///     author => "Wes Anderson",
-///     likes => 4u64
+/// 	title => "Life Aquatic",
+/// 	author => "Wes Anderson",
+/// 	likes => 4u64
 /// );
 /// # }
 /// ```

src/positions/reader.rs

@@ -36,10 +36,11 @@ struct Positions {
 
 impl Positions {
     pub fn new(position_source: ReadOnlySource, skip_source: ReadOnlySource) -> Positions {
-        let (body, footer) = skip_source.split_from_end(u32::SIZE_IN_BYTES);
+        let skip_len = skip_source.len();
+        let (body, footer) = skip_source.split(skip_len - u32::SIZE_IN_BYTES);
         let num_long_skips = u32::deserialize(&mut footer.as_slice()).expect("Index corrupted");
-        let (skip_source, long_skip_source) =
-            body.split_from_end(u64::SIZE_IN_BYTES * (num_long_skips as usize));
+        let body_split = body.len() - u64::SIZE_IN_BYTES * (num_long_skips as usize);
+        let (skip_source, long_skip_source) = body.split(body_split);
         Positions {
             bit_packer: BitPacker4x::new(),
             skip_source,

src/postings/mod.rs

@@ -75,7 +75,7 @@ pub mod tests {
         let schema = schema_builder.build();
         let index = Index::create_in_ram(schema);
         let mut segment = index.new_segment();
-        let mut posting_serializer = InvertedIndexSerializer::for_segment(&mut segment).unwrap();
+        let mut posting_serializer = InvertedIndexSerializer::open(&mut segment).unwrap();
         {
             let mut field_serializer = posting_serializer.new_field(text_field, 120 * 4).unwrap();
             field_serializer.new_term("abc".as_bytes()).unwrap();

src/postings/serializer.rs

@@ -10,8 +10,8 @@ use crate::postings::USE_SKIP_INFO_LIMIT;
 use crate::schema::Schema;
 use crate::schema::{Field, FieldEntry, FieldType};
 use crate::termdict::{TermDictionaryBuilder, TermOrdinal};
+use crate::DocId;
 use crate::Result;
-use crate::{Directory, DocId};
 use std::io::{self, Write};
 
 /// `InvertedIndexSerializer` is in charge of serializing
@@ -54,36 +54,33 @@ pub struct InvertedIndexSerializer {
 }
 
 impl InvertedIndexSerializer {
-    pub(crate) fn for_segment(segment: &mut Segment) -> crate::Result<Self> {
-        let schema = segment.schema();
-        use crate::core::SegmentComponent;
-        let terms_wrt = segment.open_write(SegmentComponent::TERMS)?;
-        let postings_wrt = segment.open_write(SegmentComponent::POSTINGS)?;
-        let positions_wrt = segment.open_write(SegmentComponent::POSITIONS)?;
-        let positions_idx_wrt = segment.open_write(SegmentComponent::POSITIONSSKIP)?;
-        Ok(Self::open(
-            schema,
-            terms_wrt,
-            postings_wrt,
-            positions_wrt,
-            positions_idx_wrt,
-        ))
-    }
-    /// Open a new `PostingsSerializer` for the given segment
-    pub(crate) fn open(
+    /// Open a new `InvertedIndexSerializer` for the given segment
+    fn create(
+        terms_write: CompositeWrite<WritePtr>,
+        postings_write: CompositeWrite<WritePtr>,
+        positions_write: CompositeWrite<WritePtr>,
+        positionsidx_write: CompositeWrite<WritePtr>,
         schema: Schema,
-        terms_wrt: WritePtr,
-        postings_wrt: WritePtr,
-        positions_wrt: WritePtr,
-        positions_idx_wrt: WritePtr,
-    ) -> InvertedIndexSerializer {
-        InvertedIndexSerializer {
-            terms_write: CompositeWrite::wrap(terms_wrt),
-            postings_write: CompositeWrite::wrap(postings_wrt),
-            positions_write: CompositeWrite::wrap(positions_wrt),
-            positionsidx_write: CompositeWrite::wrap(positions_idx_wrt),
+    ) -> Result<InvertedIndexSerializer> {
+        Ok(InvertedIndexSerializer {
+            terms_write,
+            postings_write,
+            positions_write,
+            positionsidx_write,
             schema,
-        }
+        })
+    }
+
+    /// Open a new `PostingsSerializer` for the given segment
+    pub fn open(segment: &mut Segment) -> Result<InvertedIndexSerializer> {
+        use crate::SegmentComponent::{POSITIONS, POSITIONSSKIP, POSTINGS, TERMS};
+        InvertedIndexSerializer::create(
+            CompositeWrite::wrap(segment.open_write(TERMS)?),
+            CompositeWrite::wrap(segment.open_write(POSTINGS)?),
+            CompositeWrite::wrap(segment.open_write(POSITIONS)?),
+            CompositeWrite::wrap(segment.open_write(POSITIONSSKIP)?),
+            segment.schema(),
+        )
     }
 
     /// Must be called before starting pushing terms of

src/query/exclude.rs

@@ -54,21 +54,21 @@ where
         match self.excluding_state {
             State::ExcludeOne(excluded_doc) => {
                 if doc == excluded_doc {
-                    return false;
-                }
-                if excluded_doc > doc {
-                    return true;
-                }
-                match self.excluding_docset.skip_next(doc) {
-                    SkipResult::OverStep => {
-                        self.excluding_state = State::ExcludeOne(self.excluding_docset.doc());
-                        true
+                    false
+                } else if excluded_doc > doc {
+                    true
+                } else {
+                    match self.excluding_docset.skip_next(doc) {
+                        SkipResult::OverStep => {
+                            self.excluding_state = State::ExcludeOne(self.excluding_docset.doc());
+                            true
+                        }
+                        SkipResult::End => {
+                            self.excluding_state = State::Finished;
+                            true
+                        }
+                        SkipResult::Reached => false,
                     }
-                    SkipResult::End => {
-                        self.excluding_state = State::Finished;
-                        true
-                    }
-                    SkipResult::Reached => false,
                 }
             }
             State::Finished => true,

src/query/fuzzy_query.rs

@@ -33,6 +33,7 @@ static LEV_BUILDER: Lazy<HashMap<(u8, bool), LevenshteinAutomatonBuilder>> = Laz
 /// use tantivy::schema::{Schema, TEXT};
 /// use tantivy::{doc, Index, Result, Term};
 ///
+/// # fn main() { example().unwrap(); }
 /// fn example() -> Result<()> {
 ///     let mut schema_builder = Schema::builder();
 ///     let title = schema_builder.add_text_field("title", TEXT);
@@ -58,6 +59,7 @@ static LEV_BUILDER: Lazy<HashMap<(u8, bool), LevenshteinAutomatonBuilder>> = Laz
 ///     let searcher = reader.searcher();
 ///
 ///     {
+///
 ///         let term = Term::from_field_text(title, "Diary");
 ///         let query = FuzzyTermQuery::new(term, 1, true);
 ///         let (top_docs, count) = searcher.search(&query, &(TopDocs::with_limit(2), Count)).unwrap();
@@ -67,7 +69,6 @@ static LEV_BUILDER: Lazy<HashMap<(u8, bool), LevenshteinAutomatonBuilder>> = Laz
 ///
 ///     Ok(())
 /// }
-/// # assert!(example().is_ok());
 /// ```
 #[derive(Debug, Clone)]
 pub struct FuzzyTermQuery {

src/query/phrase_query/phrase_scorer.rs

@@ -4,7 +4,6 @@ use crate::postings::Postings;
 use crate::query::bm25::BM25Weight;
 use crate::query::{Intersection, Scorer};
 use crate::DocId;
-use std::cmp::Ordering;
 
 struct PostingsWithOffset<TPostings> {
     offset: u32,
@@ -60,16 +59,12 @@ fn intersection_exists(left: &[u32], right: &[u32]) -> bool {
     while left_i < left.len() && right_i < right.len() {
         let left_val = left[left_i];
         let right_val = right[right_i];
-        match left_val.cmp(&right_val) {
-            Ordering::Less => {
-                left_i += 1;
-            }
-            Ordering::Equal => {
-                return true;
-            }
-            Ordering::Greater => {
-                right_i += 1;
-            }
+        if left_val < right_val {
+            left_i += 1;
+        } else if right_val < left_val {
+            right_i += 1;
+        } else {
+            return true;
         }
     }
     false
@@ -82,18 +77,14 @@ fn intersection_count(left: &[u32], right: &[u32]) -> usize {
     while left_i < left.len() && right_i < right.len() {
         let left_val = left[left_i];
         let right_val = right[right_i];
-        match left_val.cmp(&right_val) {
-            Ordering::Less => {
-                left_i += 1;
-            }
-            Ordering::Equal => {
-                count += 1;
-                left_i += 1;
-                right_i += 1;
-            }
-            Ordering::Greater => {
-                right_i += 1;
-            }
+        if left_val < right_val {
+            left_i += 1;
+        } else if right_val < left_val {
+            right_i += 1;
+        } else {
+            count += 1;
+            left_i += 1;
+            right_i += 1;
         }
     }
     count
@@ -112,19 +103,15 @@ fn intersection(left: &mut [u32], right: &[u32]) -> usize {
     while left_i < left_len && right_i < right_len {
         let left_val = left[left_i];
         let right_val = right[right_i];
-        match left_val.cmp(&right_val) {
-            Ordering::Less => {
-                left_i += 1;
-            }
-            Ordering::Equal => {
-                left[count] = left_val;
-                count += 1;
-                left_i += 1;
-                right_i += 1;
-            }
-            Ordering::Greater => {
-                right_i += 1;
-            }
+        if left_val < right_val {
+            left_i += 1;
+        } else if right_val < left_val {
+            right_i += 1;
+        } else {
+            left[count] = left_val;
+            count += 1;
+            left_i += 1;
+            right_i += 1;
         }
     }
     count

src/query/query_parser/query_parser.rs

@@ -8,7 +8,7 @@ use crate::query::PhraseQuery;
 use crate::query::Query;
 use crate::query::RangeQuery;
 use crate::query::TermQuery;
-use crate::schema::{Facet, IndexRecordOption};
+use crate::schema::IndexRecordOption;
 use crate::schema::{Field, Schema};
 use crate::schema::{FieldType, Term};
 use crate::tokenizer::TokenizerManager;
@@ -319,10 +319,7 @@ impl QueryParser {
                     ))
                 }
             }
-            FieldType::HierarchicalFacet => {
-                let facet = Facet::from_text(phrase);
-                Ok(vec![(0, Term::from_field_text(field, facet.encoded_str()))])
-            }
+            FieldType::HierarchicalFacet => Ok(vec![(0, Term::from_field_text(field, phrase))]),
             FieldType::Bytes => {
                 let field_name = self.schema.get_field_name(field).to_string();
                 Err(QueryParserError::FieldNotIndexed(field_name))
@@ -557,7 +554,6 @@ mod test {
         schema_builder.add_text_field("with_stop_words", text_options);
         schema_builder.add_date_field("date", INDEXED);
         schema_builder.add_f64_field("float", INDEXED);
-        schema_builder.add_facet_field("facet");
         let schema = schema_builder.build();
         let default_fields = vec![title, text];
         let tokenizer_manager = TokenizerManager::default();
@@ -592,13 +588,9 @@ mod test {
     }
 
     #[test]
-    pub fn test_parse_query_facet() {
+    pub fn test_parse_query_simple() {
         let query_parser = make_query_parser();
-        let query = query_parser.parse_query("facet:/root/branch/leaf").unwrap();
-        assert_eq!(
-            format!("{:?}", query),
-            "TermQuery(Term(field=11,bytes=[114, 111, 111, 116, 0, 98, 114, 97, 110, 99, 104, 0, 108, 101, 97, 102]))"
-        );
+        assert!(query_parser.parse_query("toto").is_ok());
     }
 
     #[test]

src/query/range_query.rs

@@ -38,33 +38,41 @@ fn map_bound<TFrom, TTo, Transform: Fn(&TFrom) -> TTo>(
 /// # Example
 ///
 /// ```rust
-/// use tantivy::collector::Count;
-/// use tantivy::query::RangeQuery;
-/// use tantivy::schema::{Schema, INDEXED};
-/// use tantivy::{doc, Index};
-/// # fn test() -> tantivy::Result<()> {
-/// let mut schema_builder = Schema::builder();
-/// let year_field = schema_builder.add_u64_field("year", INDEXED);
-/// let schema = schema_builder.build();
-///
-/// let index = Index::create_in_ram(schema);
-/// let mut index_writer = index.writer_with_num_threads(1, 6_000_000)?;
-/// for year in 1950u64..2017u64 {
-///     let num_docs_within_year = 10 + (year - 1950) * (year - 1950);
-///     for _ in 0..num_docs_within_year {
-///       index_writer.add_document(doc!(year_field => year));
-///     }
-/// }
-/// index_writer.commit()?;
-///
-/// let reader = index.reader()?;
+/// # use tantivy::collector::Count;
+/// # use tantivy::query::RangeQuery;
+/// # use tantivy::schema::{Schema, INDEXED};
+/// # use tantivy::{doc, Index, Result};
+/// #
+/// # fn run() -> Result<()> {
+/// #     let mut schema_builder = Schema::builder();
+/// #     let year_field = schema_builder.add_u64_field("year", INDEXED);
+/// #     let schema = schema_builder.build();
+/// #
+/// #     let index = Index::create_in_ram(schema);
+/// #     {
+/// #         let mut index_writer = index.writer_with_num_threads(1, 6_000_000).unwrap();
+/// #         for year in 1950u64..2017u64 {
+/// #             let num_docs_within_year = 10 + (year - 1950) * (year - 1950);
+/// #             for _ in 0..num_docs_within_year {
+/// #                 index_writer.add_document(doc!(year_field => year));
+/// #             }
+/// #         }
+/// #         index_writer.commit().unwrap();
+/// #     }
+/// #   let reader = index.reader()?;
 /// let searcher = reader.searcher();
+///
 /// let docs_in_the_sixties = RangeQuery::new_u64(year_field, 1960..1970);
+///
 /// let num_60s_books = searcher.search(&docs_in_the_sixties, &Count)?;
-/// assert_eq!(num_60s_books, 2285);
-/// Ok(())
+///
+/// #     assert_eq!(num_60s_books, 2285);
+/// #     Ok(())
+/// # }
+/// #
+/// # fn main() {
+/// #   run().unwrap()
 /// # }
-/// # assert!(test().is_ok());
 /// ```
 #[derive(Clone, Debug)]
 pub struct RangeQuery {

src/query/regex_query.rs

@@ -15,40 +15,40 @@ use tantivy_fst::Regex;
 /// use tantivy::collector::Count;
 /// use tantivy::query::RegexQuery;
 /// use tantivy::schema::{Schema, TEXT};
-/// use tantivy::{doc, Index, Term};
+/// use tantivy::{doc, Index, Result, Term};
 ///
-/// # fn test() -> tantivy::Result<()> {
-/// let mut schema_builder = Schema::builder();
-/// let title = schema_builder.add_text_field("title", TEXT);
-/// let schema = schema_builder.build();
-/// let index = Index::create_in_ram(schema);
-/// {
-///     let mut index_writer = index.writer(3_000_000)?;
-///     index_writer.add_document(doc!(
-///         title => "The Name of the Wind",
-///     ));
-///     index_writer.add_document(doc!(
-///         title => "The Diary of Muadib",
-///     ));
-///     index_writer.add_document(doc!(
-///         title => "A Dairy Cow",
-///     ));
-///     index_writer.add_document(doc!(
-///         title => "The Diary of a Young Girl",
-///     ));
-///     index_writer.commit().unwrap();
+/// # fn main() { example().unwrap(); }
+/// fn example() -> Result<()> {
+///     let mut schema_builder = Schema::builder();
+///     let title = schema_builder.add_text_field("title", TEXT);
+///     let schema = schema_builder.build();
+///     let index = Index::create_in_ram(schema);
+///     {
+///         let mut index_writer = index.writer(3_000_000)?;
+///         index_writer.add_document(doc!(
+///             title => "The Name of the Wind",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of Muadib",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "A Dairy Cow",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of a Young Girl",
+///         ));
+///         index_writer.commit().unwrap();
+///     }
+///
+///     let reader = index.reader()?;
+///     let searcher = reader.searcher();
+///
+///     let term = Term::from_field_text(title, "Diary");
+///     let query = RegexQuery::from_pattern("d[ai]{2}ry", title)?;
+///     let count = searcher.search(&query, &Count)?;
+///     assert_eq!(count, 3);
+///     Ok(())
 /// }
-///
-/// let reader = index.reader()?;
-/// let searcher = reader.searcher();
-///
-/// let term = Term::from_field_text(title, "Diary");
-/// let query = RegexQuery::from_pattern("d[ai]{2}ry", title)?;
-/// let count = searcher.search(&query, &Count)?;
-/// assert_eq!(count, 3);
-/// Ok(())
-/// # }
-/// # assert!(test().is_ok());
 /// ```
 #[derive(Debug, Clone)]
 pub struct RegexQuery {

src/query/term_query/term_query.rs

@@ -23,39 +23,42 @@ use std::fmt;
 /// use tantivy::collector::{Count, TopDocs};
 /// use tantivy::query::TermQuery;
 /// use tantivy::schema::{Schema, TEXT, IndexRecordOption};
-/// use tantivy::{doc, Index, Term};
-/// # fn test() -> tantivy::Result<()> {
-/// let mut schema_builder = Schema::builder();
-/// let title = schema_builder.add_text_field("title", TEXT);
-/// let schema = schema_builder.build();
-/// let index = Index::create_in_ram(schema);
-/// {
-///     let mut index_writer = index.writer(3_000_000)?;
-///     index_writer.add_document(doc!(
-///         title => "The Name of the Wind",
-///     ));
-///     index_writer.add_document(doc!(
-///         title => "The Diary of Muadib",
-///     ));
-///     index_writer.add_document(doc!(
-///         title => "A Dairy Cow",
-///     ));
-///     index_writer.add_document(doc!(
-///         title => "The Diary of a Young Girl",
-///     ));
-///     index_writer.commit()?;
+/// use tantivy::{doc, Index, Result, Term};
+///
+/// # fn main() { example().unwrap(); }
+/// fn example() -> Result<()> {
+///     let mut schema_builder = Schema::builder();
+///     let title = schema_builder.add_text_field("title", TEXT);
+///     let schema = schema_builder.build();
+///     let index = Index::create_in_ram(schema);
+///     {
+///         let mut index_writer = index.writer(3_000_000)?;
+///         index_writer.add_document(doc!(
+///             title => "The Name of the Wind",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of Muadib",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "A Dairy Cow",
+///         ));
+///         index_writer.add_document(doc!(
+///             title => "The Diary of a Young Girl",
+///         ));
+///         index_writer.commit()?;
+///     }
+///     let reader = index.reader()?;
+///     let searcher = reader.searcher();
+///
+///     let query = TermQuery::new(
+///         Term::from_field_text(title, "diary"),
+///         IndexRecordOption::Basic,
+///     );
+///     let (top_docs, count) = searcher.search(&query, &(TopDocs::with_limit(2), Count)).unwrap();
+///     assert_eq!(count, 2);
+///
+///     Ok(())
 /// }
-/// let reader = index.reader()?;
-/// let searcher = reader.searcher();
-/// let query = TermQuery::new(
-///     Term::from_field_text(title, "diary"),
-///     IndexRecordOption::Basic,
-/// );
-/// let (top_docs, count) = searcher.search(&query, &(TopDocs::with_limit(2), Count))?;
-/// assert_eq!(count, 2);
-/// Ok(())
-/// # }
-/// # assert!(test().is_ok());
 /// ```
 #[derive(Clone)]
 pub struct TermQuery {

src/reader/mod.rs

@@ -162,11 +162,6 @@ pub struct IndexReader {
 }
 
 impl IndexReader {
-    #[cfg(test)]
-    pub(crate) fn index(&self) -> Index {
-        self.inner.index.clone()
-    }
-
     /// Update searchers so that they reflect the state of the last
     /// `.commit()`.
     ///

src/reader/pool.rs

@@ -167,7 +167,7 @@ mod tests {
 
     use super::Pool;
     use super::Queue;
-    use std::{iter, mem};
+    use std::iter;
 
     #[test]
     fn test_pool() {
@@ -197,67 +197,33 @@ mod tests {
     fn test_pool_dont_panic_on_empty_pop() {
         // When the object pool is exhausted, it shouldn't panic on pop()
         use std::sync::Arc;
-        use std::thread;
+        use std::{thread, time};
 
         // Wrap the pool in an Arc, same way as its used in `core/index.rs`
-        let pool1 = Arc::new(Pool::new());
+        let pool = Arc::new(Pool::new());
         // clone pools outside the move scope of each new thread
-        let pool2 = Arc::clone(&pool1);
-        let pool3 = Arc::clone(&pool1);
-
+        let pool1 = Arc::clone(&pool);
+        let pool2 = Arc::clone(&pool);
         let elements_for_pool = vec![1, 2];
-        pool1.publish_new_generation(elements_for_pool);
+        pool.publish_new_generation(elements_for_pool);
 
         let mut threads = vec![];
+        let sleep_dur = time::Duration::from_millis(10);
         // spawn one more thread than there are elements in the pool
-
-        let (start_1_send, start_1_recv) = crossbeam::bounded(0);
-        let (start_2_send, start_2_recv) = crossbeam::bounded(0);
-        let (start_3_send, start_3_recv) = crossbeam::bounded(0);
-
-        let (event_send1, event_recv) = crossbeam::unbounded();
-        let event_send2 = event_send1.clone();
-        let event_send3 = event_send1.clone();
-
         threads.push(thread::spawn(move || {
-            assert_eq!(start_1_recv.recv(), Ok("start"));
+            // leasing to make sure it's not dropped before sleep is called
+            let _leased_searcher = &pool.acquire();
+            thread::sleep(sleep_dur);
+        }));
+        threads.push(thread::spawn(move || {
+            // leasing to make sure it's not dropped before sleep is called
             let _leased_searcher = &pool1.acquire();
-            assert!(event_send1.send("1 acquired").is_ok());
-            assert_eq!(start_1_recv.recv(), Ok("stop"));
-            assert!(event_send1.send("1 stopped").is_ok());
-            mem::drop(_leased_searcher);
+            thread::sleep(sleep_dur);
         }));
-
         threads.push(thread::spawn(move || {
-            assert_eq!(start_2_recv.recv(), Ok("start"));
+            // leasing to make sure it's not dropped before sleep is called
             let _leased_searcher = &pool2.acquire();
-            assert!(event_send2.send("2 acquired").is_ok());
-            assert_eq!(start_2_recv.recv(), Ok("stop"));
-            mem::drop(_leased_searcher);
-            assert!(event_send2.send("2 stopped").is_ok());
+            thread::sleep(sleep_dur);
         }));
-
-        threads.push(thread::spawn(move || {
-            assert_eq!(start_3_recv.recv(), Ok("start"));
-            let _leased_searcher = &pool3.acquire();
-            assert!(event_send3.send("3 acquired").is_ok());
-            assert_eq!(start_3_recv.recv(), Ok("stop"));
-            mem::drop(_leased_searcher);
-            assert!(event_send3.send("3 stopped").is_ok());
-        }));
-
-        assert!(start_1_send.send("start").is_ok());
-        assert_eq!(event_recv.recv(), Ok("1 acquired"));
-        assert!(start_2_send.send("start").is_ok());
-        assert_eq!(event_recv.recv(), Ok("2 acquired"));
-        assert!(start_3_send.send("start").is_ok());
-        assert!(event_recv.try_recv().is_err());
-        assert!(start_1_send.send("stop").is_ok());
-        assert_eq!(event_recv.recv(), Ok("1 stopped"));
-        assert_eq!(event_recv.recv(), Ok("3 acquired"));
-        assert!(start_3_send.send("stop").is_ok());
-        assert_eq!(event_recv.recv(), Ok("3 stopped"));
-        assert!(start_2_send.send("stop").is_ok());
-        assert_eq!(event_recv.recv(), Ok("2 stopped"));
     }
 }

src/schema/document.rs

@@ -1,7 +1,6 @@
 use super::*;
 use crate::common::BinarySerializable;
 use crate::common::VInt;
-use crate::tokenizer::PreTokenizedString;
 use crate::DateTime;
 use itertools::Itertools;
 use std::io::{self, Read, Write};
@@ -30,8 +29,8 @@ impl From<Vec<FieldValue>> for Document {
 impl PartialEq for Document {
     fn eq(&self, other: &Document) -> bool {
         // super slow, but only here for tests
-        let mut self_field_values: Vec<&_> = self.field_values.iter().collect();
-        let mut other_field_values: Vec<&_> = other.field_values.iter().collect();
+        let mut self_field_values = self.field_values.clone();
+        let mut other_field_values = other.field_values.clone();
         self_field_values.sort();
         other_field_values.sort();
         self_field_values.eq(&other_field_values)
@@ -79,16 +78,6 @@ impl Document {
         self.add(FieldValue::new(field, value));
     }
 
-    /// Add a pre-tokenized text field.
-    pub fn add_pre_tokenized_text(
-        &mut self,
-        field: Field,
-        pre_tokenized_text: &PreTokenizedString,
-    ) {
-        let value = Value::PreTokStr(pre_tokenized_text.clone());
-        self.add(FieldValue::new(field, value));
-    }
-
     /// Add a u64 field
     pub fn add_u64(&mut self, field: Field, value: u64) {
         self.add(FieldValue::new(field, Value::U64(value)));
@@ -155,21 +144,6 @@ impl Document {
             .find(|field_value| field_value.field() == field)
             .map(FieldValue::value)
     }
-
-    /// Prepares Document for being stored in the document store
-    ///
-    /// Method transforms PreTokenizedString values into String
-    /// values.
-    pub fn prepare_for_store(&mut self) {
-        for field_value in &mut self.field_values {
-            if let Value::PreTokStr(pre_tokenized_text) = field_value.value() {
-                *field_value = FieldValue::new(
-                    field_value.field(),
-                    Value::Str(pre_tokenized_text.text.clone()), //< TODO somehow remove .clone()
-                );
-            }
-        }
-    }
 }
 
 impl BinarySerializable for Document {
@@ -195,7 +169,6 @@ impl BinarySerializable for Document {
 mod tests {
 
     use crate::schema::*;
-    use crate::tokenizer::{PreTokenizedString, Token};
 
     #[test]
     fn test_doc() {
@@ -205,38 +178,4 @@ mod tests {
         doc.add_text(text_field, "My title");
         assert_eq!(doc.field_values().len(), 1);
     }
-
-    #[test]
-    fn test_prepare_for_store() {
-        let mut schema_builder = Schema::builder();
-        let text_field = schema_builder.add_text_field("title", TEXT);
-        let mut doc = Document::default();
-
-        let pre_tokenized_text = PreTokenizedString {
-            text: String::from("A"),
-            tokens: vec![Token {
-                offset_from: 0,
-                offset_to: 1,
-                position: 0,
-                text: String::from("A"),
-                position_length: 1,
-            }],
-        };
-
-        doc.add_pre_tokenized_text(text_field, &pre_tokenized_text);
-        doc.add_text(text_field, "title");
-        doc.prepare_for_store();
-
-        assert_eq!(doc.field_values().len(), 2);
-
-        match doc.field_values()[0].value() {
-            Value::Str(ref text) => assert_eq!(text, "A"),
-            _ => panic!("Incorrect variant of Value"),
-        }
-
-        match doc.field_values()[1].value() {
-            Value::Str(ref text) => assert_eq!(text, "title"),
-            _ => panic!("Incorrect variant of Value"),
-        }
-    }
 }

src/schema/field.rs

@@ -15,7 +15,6 @@ impl Field {
     }
 
     /// Returns a u32 identifying uniquely a field within a schema.
-    #[allow(clippy::trivially_copy_pass_by_ref)]
     pub fn field_id(&self) -> u32 {
         self.0
     }

src/schema/field_type.rs

@@ -1,12 +1,11 @@
 use base64::decode;
 
+use crate::schema::{IntOptions, TextOptions};
+
 use crate::schema::Facet;
 use crate::schema::IndexRecordOption;
 use crate::schema::TextFieldIndexing;
 use crate::schema::Value;
-use crate::schema::{IntOptions, TextOptions};
-use crate::tokenizer::PreTokenizedString;
-use chrono::{FixedOffset, Utc};
 use serde_json::Value as JsonValue;
 
 /// Possible error that may occur while parsing a field value
@@ -125,20 +124,13 @@ impl FieldType {
     pub fn value_from_json(&self, json: &JsonValue) -> Result<Value, ValueParsingError> {
         match *json {
             JsonValue::String(ref field_text) => match *self {
-                FieldType::Date(_) => {
-                    let dt_with_fixed_tz: chrono::DateTime<FixedOffset> =
-                        chrono::DateTime::parse_from_rfc3339(field_text).map_err(|err|
-                            ValueParsingError::TypeError(format!(
-                                "Failed to parse date from JSON. Expected rfc3339 format, got {}. {:?}",
-                                field_text, err
-                            ))
-                        )?;
-                    Ok(Value::Date(dt_with_fixed_tz.with_timezone(&Utc)))
-                }
                 FieldType::Str(_) => Ok(Value::Str(field_text.clone())),
-                FieldType::U64(_) | FieldType::I64(_) | FieldType::F64(_) => Err(
-                    ValueParsingError::TypeError(format!("Expected an integer, got {:?}", json)),
-                ),
+                FieldType::U64(_) | FieldType::I64(_) | FieldType::F64(_) | FieldType::Date(_) => {
+                    Err(ValueParsingError::TypeError(format!(
+                        "Expected an integer, got {:?}",
+                        json
+                    )))
+                }
                 FieldType::HierarchicalFacet => Ok(Value::Facet(Facet::from(field_text))),
                 FieldType::Bytes => decode(field_text).map(Value::Bytes).map_err(|_| {
                     ValueParsingError::InvalidBase64(format!(
@@ -177,28 +169,6 @@ impl FieldType {
                     Err(ValueParsingError::TypeError(msg))
                 }
             },
-            JsonValue::Object(_) => match *self {
-                FieldType::Str(_) => {
-                    if let Ok(tok_str_val) =
-                        serde_json::from_value::<PreTokenizedString>(json.clone())
-                    {
-                        Ok(Value::PreTokStr(tok_str_val))
-                    } else {
-                        let msg = format!(
-                            "Json value {:?} cannot be translated to PreTokenizedString.",
-                            json
-                        );
-                        Err(ValueParsingError::TypeError(msg))
-                    }
-                }
-                _ => {
-                    let msg = format!(
-                        "Json value not supported error {:?}. Expected {:?}",
-                        json, self
-                    );
-                    Err(ValueParsingError::TypeError(msg))
-                }
-            },
             _ => {
                 let msg = format!(
                     "Json value not supported error {:?}. Expected {:?}",
@@ -214,37 +184,7 @@ impl FieldType {
 mod tests {
     use super::FieldType;
     use crate::schema::field_type::ValueParsingError;
-    use crate::schema::TextOptions;
     use crate::schema::Value;
-    use crate::schema::{Schema, INDEXED};
-    use crate::tokenizer::{PreTokenizedString, Token};
-    use crate::{DateTime, Document};
-    use chrono::{NaiveDate, NaiveDateTime, NaiveTime, Utc};
-
-    #[test]
-    fn test_deserialize_json_date() {
-        let mut schema_builder = Schema::builder();
-        let date_field = schema_builder.add_date_field("date", INDEXED);
-        let schema = schema_builder.build();
-        let doc_json = r#"{"date": "2019-10-12T07:20:50.52+02:00"}"#;
-        let doc = schema.parse_document(doc_json).unwrap();
-        let date = doc.get_first(date_field).unwrap();
-        assert_eq!(format!("{:?}", date), "Date(2019-10-12T05:20:50.520Z)");
-    }
-
-    #[test]
-    fn test_serialize_json_date() {
-        let mut doc = Document::new();
-        let mut schema_builder = Schema::builder();
-        let date_field = schema_builder.add_date_field("date", INDEXED);
-        let schema = schema_builder.build();
-        let naive_date = NaiveDate::from_ymd(1982, 9, 17);
-        let naive_time = NaiveTime::from_hms(13, 20, 00);
-        let date_time = DateTime::from_utc(NaiveDateTime::new(naive_date, naive_time), Utc);
-        doc.add_date(date_field, &date_time);
-        let doc_json = schema.to_json(&doc);
-        assert_eq!(doc_json, r#"{"date":["1982-09-17T13:20:00+00:00"]}"#);
-    }
 
     #[test]
     fn test_bytes_value_from_json() {
@@ -265,71 +205,4 @@ mod tests {
             _ => panic!("Expected parse failure for invalid base64"),
         }
     }
-
-    #[test]
-    fn test_pre_tok_str_value_from_json() {
-        let pre_tokenized_string_json = r#"{
-  "text": "The Old Man",
-  "tokens": [
-    {
-      "offset_from": 0,
-      "offset_to": 3,
-      "position": 0,
-      "text": "The",
-      "position_length": 1
-    },
-    {
-      "offset_from": 4,
-      "offset_to": 7,
-      "position": 1,
-      "text": "Old",
-      "position_length": 1
-    },
-    {
-      "offset_from": 8,
-      "offset_to": 11,
-      "position": 2,
-      "text": "Man",
-      "position_length": 1
-    }
-  ]
-}"#;
-
-        let expected_value = Value::PreTokStr(PreTokenizedString {
-            text: String::from("The Old Man"),
-            tokens: vec![
-                Token {
-                    offset_from: 0,
-                    offset_to: 3,
-                    position: 0,
-                    text: String::from("The"),
-                    position_length: 1,
-                },
-                Token {
-                    offset_from: 4,
-                    offset_to: 7,
-                    position: 1,
-                    text: String::from("Old"),
-                    position_length: 1,
-                },
-                Token {
-                    offset_from: 8,
-                    offset_to: 11,
-                    position: 2,
-                    text: String::from("Man"),
-                    position_length: 1,
-                },
-            ],
-        });
-
-        let deserialized_value = FieldType::Str(TextOptions::default())
-            .value_from_json(&serde_json::from_str(pre_tokenized_string_json).unwrap())
-            .unwrap();
-
-        assert_eq!(deserialized_value, expected_value);
-
-        let serialized_value_json = serde_json::to_string_pretty(&expected_value).unwrap();
-
-        assert_eq!(serialized_value_json, pre_tokenized_string_json);
-    }
 }

src/schema/flags.rs

@@ -53,7 +53,7 @@ where
     fn bitor(self, head: SchemaFlagList<Head, ()>) -> Self::Output {
         SchemaFlagList {
             head: head.head,
-            tail: self,
+            tail: self.clone(),
         }
     }
 }

src/schema/mod.rs

@@ -44,7 +44,7 @@ We can split the problem of generating a search result page into two phases :
   the search results page. (`doc_ids[] -> Document[]`)
 
 In the first phase, the ability to search for documents by the given field is determined by the
-[`IndexRecordOption`](enum.IndexRecordOption.html) of our
+[`TextIndexingOptions`](enum.TextIndexingOptions.html) of our
 [`TextOptions`](struct.TextOptions.html).
 
 The effect of each possible setting is described more in detail

src/schema/schema.rs

@@ -166,7 +166,7 @@ impl SchemaBuilder {
     }
 
     /// Adds a field entry to the schema in build.
-    pub fn add_field(&mut self, field_entry: FieldEntry) -> Field {
+    fn add_field(&mut self, field_entry: FieldEntry) -> Field {
         let field = Field::from_field_id(self.fields.len() as u32);
         let field_name = field_entry.name().to_string();
         self.fields.push(field_entry);
@@ -401,7 +401,6 @@ pub enum DocParsingError {
 mod tests {
 
     use crate::schema::field_type::ValueParsingError;
-    use crate::schema::int_options::Cardinality::SingleValue;
     use crate::schema::schema::DocParsingError::NotJSON;
     use crate::schema::*;
     use matches::{assert_matches, matches};
@@ -716,94 +715,4 @@ mod tests {
             assert_matches!(json_err, Err(NotJSON(_)));
         }
     }
-
-    #[test]
-    pub fn test_schema_add_field() {
-        let mut schema_builder = SchemaBuilder::default();
-        let id_options = TextOptions::default().set_stored().set_indexing_options(
-            TextFieldIndexing::default()
-                .set_tokenizer("raw")
-                .set_index_option(IndexRecordOption::Basic),
-        );
-        let timestamp_options = IntOptions::default()
-            .set_stored()
-            .set_indexed()
-            .set_fast(SingleValue);
-        schema_builder.add_text_field("_id", id_options);
-        schema_builder.add_date_field("_timestamp", timestamp_options);
-
-        let schema_content = r#"[
-  {
-    "name": "text",
-    "type": "text",
-    "options": {
-      "indexing": {
-        "record": "position",
-        "tokenizer": "default"
-      },
-      "stored": false
-    }
-  },
-  {
-    "name": "popularity",
-    "type": "i64",
-    "options": {
-      "indexed": false,
-      "fast": "single",
-      "stored": true
-    }
-  }
-]"#;
-        let tmp_schema: Schema =
-            serde_json::from_str(&schema_content).expect("error while reading json");
-        for (_field, field_entry) in tmp_schema.fields() {
-            schema_builder.add_field(field_entry.clone());
-        }
-
-        let schema = schema_builder.build();
-        let schema_json = serde_json::to_string_pretty(&schema).unwrap();
-        let expected = r#"[
-  {
-    "name": "_id",
-    "type": "text",
-    "options": {
-      "indexing": {
-        "record": "basic",
-        "tokenizer": "raw"
-      },
-      "stored": true
-    }
-  },
-  {
-    "name": "_timestamp",
-    "type": "date",
-    "options": {
-      "indexed": true,
-      "fast": "single",
-      "stored": true
-    }
-  },
-  {
-    "name": "text",
-    "type": "text",
-    "options": {
-      "indexing": {
-        "record": "position",
-        "tokenizer": "default"
-      },
-      "stored": false
-    }
-  },
-  {
-    "name": "popularity",
-    "type": "i64",
-    "options": {
-      "indexed": false,
-      "fast": "single",
-      "stored": true
-    }
-  }
-]"#;
-        assert_eq!(schema_json, expected);
-    }
 }

src/schema/value.rs

@@ -1,5 +1,4 @@
 use crate::schema::Facet;
-use crate::tokenizer::PreTokenizedString;
 use crate::DateTime;
 use serde::de::Visitor;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
@@ -11,8 +10,6 @@ use std::{cmp::Ordering, fmt};
 pub enum Value {
     /// The str type is used for any text information.
     Str(String),
-    /// Pre-tokenized str type,
-    PreTokStr(PreTokenizedString),
     /// Unsigned 64-bits Integer `u64`
     U64(u64),
     /// Signed 64-bits Integer `i64`
@@ -32,7 +29,6 @@ impl Ord for Value {
     fn cmp(&self, other: &Self) -> Ordering {
         match (self, other) {
             (Value::Str(l), Value::Str(r)) => l.cmp(r),
-            (Value::PreTokStr(l), Value::PreTokStr(r)) => l.cmp(r),
             (Value::U64(l), Value::U64(r)) => l.cmp(r),
             (Value::I64(l), Value::I64(r)) => l.cmp(r),
             (Value::Date(l), Value::Date(r)) => l.cmp(r),
@@ -48,8 +44,6 @@ impl Ord for Value {
             }
             (Value::Str(_), _) => Ordering::Less,
             (_, Value::Str(_)) => Ordering::Greater,
-            (Value::PreTokStr(_), _) => Ordering::Less,
-            (_, Value::PreTokStr(_)) => Ordering::Greater,
             (Value::U64(_), _) => Ordering::Less,
             (_, Value::U64(_)) => Ordering::Greater,
             (Value::I64(_), _) => Ordering::Less,
@@ -71,11 +65,10 @@ impl Serialize for Value {
     {
         match *self {
             Value::Str(ref v) => serializer.serialize_str(v),
-            Value::PreTokStr(ref v) => v.serialize(serializer),
             Value::U64(u) => serializer.serialize_u64(u),
             Value::I64(u) => serializer.serialize_i64(u),
             Value::F64(u) => serializer.serialize_f64(u),
-            Value::Date(ref date) => serializer.serialize_str(&date.to_rfc3339()),
+            Value::Date(ref date) => serializer.serialize_i64(date.timestamp()),
             Value::Facet(ref facet) => facet.serialize(serializer),
             Value::Bytes(ref bytes) => serializer.serialize_bytes(bytes),
         }
@@ -96,14 +89,14 @@ impl<'de> Deserialize<'de> for Value {
                 formatter.write_str("a string or u32")
             }
 
-            fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E> {
-                Ok(Value::I64(v))
-            }
-
             fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E> {
                 Ok(Value::U64(v))
             }
 
+            fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E> {
+                Ok(Value::I64(v))
+            }
+
             fn visit_f64<E>(self, v: f64) -> Result<Self::Value, E> {
                 Ok(Value::F64(v))
             }
@@ -131,15 +124,6 @@ impl Value {
         }
     }
 
-    /// Returns the tokenized text, provided the value is of the `PreTokStr` type.
-    /// (Returns None if the value is not of the `PreTokStr` type).
-    pub fn tokenized_text(&self) -> Option<&PreTokenizedString> {
-        match *self {
-            Value::PreTokStr(ref tok_text) => Some(tok_text),
-            _ => None,
-        }
-    }
-
     /// Returns the u64-value, provided the value is of the `U64` type.
     ///
     /// # Panics
@@ -209,8 +193,8 @@ impl From<f64> for Value {
     }
 }
 
-impl From<crate::DateTime> for Value {
-    fn from(date_time: crate::DateTime) -> Value {
+impl From<DateTime> for Value {
+    fn from(date_time: DateTime) -> Value {
         Value::Date(date_time)
     }
 }
@@ -233,17 +217,10 @@ impl From<Vec<u8>> for Value {
     }
 }
 
-impl From<PreTokenizedString> for Value {
-    fn from(pretokenized_string: PreTokenizedString) -> Value {
-        Value::PreTokStr(pretokenized_string)
-    }
-}
-
 mod binary_serialize {
     use super::Value;
     use crate::common::{f64_to_u64, u64_to_f64, BinarySerializable};
     use crate::schema::Facet;
-    use crate::tokenizer::PreTokenizedString;
     use chrono::{TimeZone, Utc};
     use std::io::{self, Read, Write};
 
@@ -254,11 +231,6 @@ mod binary_serialize {
     const BYTES_CODE: u8 = 4;
     const DATE_CODE: u8 = 5;
     const F64_CODE: u8 = 6;
-    const EXT_CODE: u8 = 7;
-
-    // extended types
-
-    const TOK_STR_CODE: u8 = 0;
 
     impl BinarySerializable for Value {
         fn serialize<W: Write>(&self, writer: &mut W) -> io::Result<()> {
@@ -267,18 +239,6 @@ mod binary_serialize {
                     TEXT_CODE.serialize(writer)?;
                     text.serialize(writer)
                 }
-                Value::PreTokStr(ref tok_str) => {
-                    EXT_CODE.serialize(writer)?;
-                    TOK_STR_CODE.serialize(writer)?;
-                    if let Ok(text) = serde_json::to_string(tok_str) {
-                        text.serialize(writer)
-                    } else {
-                        Err(io::Error::new(
-                            io::ErrorKind::Other,
-                            "Failed to dump Value::PreTokStr(_) to json.",
-                        ))
-                    }
-                }
                 Value::U64(ref val) => {
                     U64_CODE.serialize(writer)?;
                     val.serialize(writer)
@@ -330,30 +290,6 @@ mod binary_serialize {
                 }
                 HIERARCHICAL_FACET_CODE => Ok(Value::Facet(Facet::deserialize(reader)?)),
                 BYTES_CODE => Ok(Value::Bytes(Vec::<u8>::deserialize(reader)?)),
-                EXT_CODE => {
-                    let ext_type_code = u8::deserialize(reader)?;
-                    match ext_type_code {
-                        TOK_STR_CODE => {
-                            let str_val = String::deserialize(reader)?;
-                            if let Ok(value) = serde_json::from_str::<PreTokenizedString>(&str_val)
-                            {
-                                Ok(Value::PreTokStr(value))
-                            } else {
-                                Err(io::Error::new(
-                                    io::ErrorKind::Other,
-                                    "Failed to parse string data as Value::PreTokStr(_).",
-                                ))
-                            }
-                        }
-                        _ => Err(io::Error::new(
-                            io::ErrorKind::InvalidData,
-                            format!(
-                                "No extened field type is associated with code {:?}",
-                                ext_type_code
-                            ),
-                        )),
-                    }
-                }
                 _ => Err(io::Error::new(
                     io::ErrorKind::InvalidData,
                     format!("No field type is associated with code {:?}", type_code),
@@ -362,17 +298,3 @@ mod binary_serialize {
         }
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::Value;
-    use crate::DateTime;
-    use std::str::FromStr;
-
-    #[test]
-    fn test_serialize_date() {
-        let value = Value::Date(DateTime::from_str("1996-12-20T00:39:57+00:00").unwrap());
-        let serialized_value_json = serde_json::to_string_pretty(&value).unwrap();
-        assert_eq!(serialized_value_json, r#""1996-12-20T00:39:57+00:00""#);
-    }
-}

src/snippet/mod.rs

@@ -331,8 +331,9 @@ mod tests {
     use std::collections::BTreeMap;
     use std::iter::Iterator;
 
-    const TEST_TEXT: &'static str = r#"Rust is a systems programming language sponsored by
-Mozilla which describes it as a "safe, concurrent, practical language", supporting functional and
+    const TEST_TEXT: &'static str =
+        r#"Rust is a systems programming language sponsored by Mozilla which
+describes it as a "safe, concurrent, practical language", supporting functional and
 imperative-procedural paradigms. Rust is syntactically similar to C++[according to whom?],
 but its designers intend it to provide better memory safety while still maintaining
 performance.
@@ -362,13 +363,13 @@ Survey in 2016, 2017, and 2018."#;
         let snippet = select_best_fragment_combination(&fragments[..], &TEST_TEXT);
         assert_eq!(
             snippet.fragments,
-            "Rust is a systems programming language sponsored by\n\
-             Mozilla which describes it as a \"safe"
+            "Rust is a systems programming language sponsored by \
+             Mozilla which\ndescribes it as a \"safe"
         );
         assert_eq!(
             snippet.to_html(),
             "<b>Rust</b> is a systems programming <b>language</b> \
-             sponsored by\nMozilla which describes it as a &quot;safe"
+             sponsored by Mozilla which\ndescribes it as a &quot;safe"
         )
     }
 

src/store/compression_lz4.rs

@@ -1,9 +1,6 @@
-use std::io::{self, Read, Write};
+extern crate lz4;
 
-/// Name of the compression scheme used in the doc store.
-///
-/// This name is appended to the version string of tantivy.
-pub const COMPRESSION: &'static str = "lz4";
+use std::io::{self, Read, Write};
 
 pub fn compress(uncompressed: &[u8], compressed: &mut Vec<u8>) -> io::Result<()> {
     compressed.clear();

src/store/compression_snap.rs

@@ -2,11 +2,6 @@ use snap;
 
 use std::io::{self, Read, Write};
 
-/// Name of the compression scheme used in the doc store.
-///
-/// This name is appended to the version string of tantivy.
-pub const COMPRESSION: &str = "snappy";
-
 pub fn compress(uncompressed: &[u8], compressed: &mut Vec<u8>) -> io::Result<()> {
     compressed.clear();
     let mut encoder = snap::Writer::new(compressed);

src/store/mod.rs

@@ -42,22 +42,18 @@ pub use self::writer::StoreWriter;
 #[cfg(feature = "lz4")]
 mod compression_lz4;
 #[cfg(feature = "lz4")]
-pub use self::compression_lz4::COMPRESSION;
-#[cfg(feature = "lz4")]
-use self::compression_lz4::{compress, decompress};
+use self::compression_lz4::*;
 
 #[cfg(not(feature = "lz4"))]
 mod compression_snap;
 #[cfg(not(feature = "lz4"))]
-pub use self::compression_snap::COMPRESSION;
-#[cfg(not(feature = "lz4"))]
-use self::compression_snap::{compress, decompress};
+use self::compression_snap::*;
 
 #[cfg(test)]
 pub mod tests {
 
     use super::*;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, WritePtr};
+    use crate::directory::{Directory, RAMDirectory, WritePtr};
     use crate::schema::Document;
     use crate::schema::FieldValue;
     use crate::schema::Schema;

src/termdict/mod.rs

@@ -36,7 +36,7 @@ pub use self::termdict::{TermDictionary, TermDictionaryBuilder};
 mod tests {
     use super::{TermDictionary, TermDictionaryBuilder, TermStreamer};
     use crate::core::Index;
-    use crate::directory::{Directory, RAMDirectory, ReadOnlyDirectory, ReadOnlySource};
+    use crate::directory::{Directory, RAMDirectory, ReadOnlySource};
     use crate::postings::TermInfo;
     use crate::schema::{Document, FieldType, Schema, TEXT};
     use std::path::PathBuf;

src/tokenizer/alphanum_only.rs

@@ -2,6 +2,8 @@
 //! ```rust
 //! use tantivy::tokenizer::*;
 //!
+//! # fn main() {
+//!
 //! let tokenizer = RawTokenizer
 //!   .filter(AlphaNumOnlyFilter);
 //!
@@ -18,6 +20,7 @@
 //! assert!(stream.next().is_some());
 //! // the "emoji" is dropped because its not an alphanum
 //! assert!(stream.next().is_none());
+//! # }
 //! ```
 use super::{Token, TokenFilter, TokenStream};
 

src/tokenizer/mod.rs

@@ -7,6 +7,7 @@
 //! ```rust
 //! use tantivy::schema::*;
 //!
+//! # fn main() {
 //! let mut schema_builder = Schema::builder();
 //!
 //! let text_options = TextOptions::default()
@@ -30,6 +31,7 @@
 //! schema_builder.add_text_field("uuid", id_options);
 //!
 //! let schema = schema_builder.build();
+//! # }
 //! ```
 //!
 //! By default, `tantivy` offers the following tokenizers:
@@ -64,10 +66,12 @@
 //! ```rust
 //! use tantivy::tokenizer::*;
 //!
+//! # fn main() {
 //! let en_stem = SimpleTokenizer
 //!     .filter(RemoveLongFilter::limit(40))
 //!     .filter(LowerCaser)
 //!     .filter(Stemmer::new(Language::English));
+//! # }
 //! ```
 //!
 //! Once your tokenizer is defined, you need to
@@ -77,12 +81,13 @@
 //! # use tantivy::schema::Schema;
 //! # use tantivy::tokenizer::*;
 //! # use tantivy::Index;
-//! #
-//! let custom_en_tokenizer = SimpleTokenizer;
+//! # fn main() {
+//! # let custom_en_tokenizer = SimpleTokenizer;
 //! # let schema = Schema::builder().build();
 //! let index = Index::create_in_ram(schema);
 //! index.tokenizers()
 //!      .register("custom_en", custom_en_tokenizer);
+//! # }
 //! ```
 //!
 //! If you built your schema programmatically, a complete example
@@ -97,6 +102,7 @@
 //! use tantivy::tokenizer::*;
 //! use tantivy::Index;
 //!
+//! # fn main() {
 //! let mut schema_builder = Schema::builder();
 //! let text_field_indexing = TextFieldIndexing::default()
 //!     .set_tokenizer("custom_en")
@@ -115,6 +121,8 @@
 //! index
 //!     .tokenizers()
 //!     .register("custom_en", custom_en_tokenizer);
+//! // ...
+//! # }
 //! ```
 //!
 mod alphanum_only;
@@ -128,7 +136,6 @@ mod simple_tokenizer;
 mod stemmer;
 mod stop_word_filter;
 mod token_stream_chain;
-mod tokenized_string;
 mod tokenizer;
 mod tokenizer_manager;
 
@@ -145,9 +152,7 @@ pub use self::stop_word_filter::StopWordFilter;
 pub(crate) use self::token_stream_chain::TokenStreamChain;
 pub use self::tokenizer::BoxedTokenizer;
 
-pub use self::tokenized_string::{PreTokenizedStream, PreTokenizedString};
 pub use self::tokenizer::{Token, TokenFilter, TokenStream, Tokenizer};
-
 pub use self::tokenizer_manager::TokenizerManager;
 
 /// Maximum authorized len (in bytes) for a token.

src/tokenizer/ngram_tokenizer.rs

@@ -31,7 +31,7 @@ use super::{Token, TokenStream, Tokenizer};
 ///
 /// ```rust
 /// use tantivy::tokenizer::*;
-///
+/// # fn main() {
 /// let tokenizer = NgramTokenizer::new(2, 3, false);
 /// let mut stream = tokenizer.token_stream("hello");
 /// {
@@ -77,6 +77,7 @@ use super::{Token, TokenStream, Tokenizer};
 ///   assert_eq!(token.offset_to, 5);
 /// }
 /// assert!(stream.next().is_none());
+/// # }
 /// ```
 #[derive(Clone)]
 pub struct NgramTokenizer {

src/tokenizer/remove_long.rs

@@ -2,6 +2,8 @@
 //! ```rust
 //! use tantivy::tokenizer::*;
 //!
+//! # fn main() {
+//!
 //! let tokenizer = SimpleTokenizer
 //!   .filter(RemoveLongFilter::limit(5));
 //!
@@ -10,6 +12,7 @@
 //! // out of the token stream.
 //! assert_eq!(stream.next().unwrap().text, "nice");
 //! assert!(stream.next().is_none());
+//! # }
 //! ```
 //!
 use super::{Token, TokenFilter, TokenStream};

src/tokenizer/stemmer.rs

@@ -15,7 +15,6 @@ pub enum Language {
     Greek,
     Hungarian,
     Italian,
-    Norwegian,
     Portuguese,
     Romanian,
     Russian,
@@ -39,7 +38,6 @@ impl Language {
             Greek => Algorithm::Greek,
             Hungarian => Algorithm::Hungarian,
             Italian => Algorithm::Italian,
-            Norwegian => Algorithm::Norwegian,
             Portuguese => Algorithm::Portuguese,
             Romanian => Algorithm::Romanian,
             Russian => Algorithm::Russian,

src/tokenizer/stop_word_filter.rs

@@ -2,6 +2,7 @@
 //! ```rust
 //! use tantivy::tokenizer::*;
 //!
+//! # fn main() {
 //! let tokenizer = SimpleTokenizer
 //!   .filter(StopWordFilter::remove(vec!["the".to_string(), "is".to_string()]));
 //!
@@ -9,6 +10,7 @@
 //! assert_eq!(stream.next().unwrap().text, "fox");
 //! assert_eq!(stream.next().unwrap().text, "crafty");
 //! assert!(stream.next().is_none());
+//! # }
 //! ```
 use super::{Token, TokenFilter, TokenStream};
 use fnv::FnvHasher;
@@ -44,7 +46,7 @@ impl StopWordFilter {
             "there", "these", "they", "this", "to", "was", "will", "with",
         ];
 
-        StopWordFilter::remove(words.iter().map(|&s| s.to_string()).collect())
+        StopWordFilter::remove(words.iter().map(|s| s.to_string()).collect())
     }
 }
 

src/tokenizer/tokenized_string.rs

@@ -1,189 +0,0 @@
-use crate::tokenizer::{Token, TokenStream, TokenStreamChain};
-use std::cmp::Ordering;
-
-/// Struct representing pre-tokenized text
-#[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq)]
-pub struct PreTokenizedString {
-    /// Original text
-    pub text: String,
-    /// Tokens derived from the text
-    pub tokens: Vec<Token>,
-}
-
-impl Ord for PreTokenizedString {
-    fn cmp(&self, other: &Self) -> Ordering {
-        self.text.cmp(&other.text)
-    }
-}
-
-impl PartialOrd for PreTokenizedString {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        Some(self.cmp(other))
-    }
-}
-
-/// TokenStream implementation which wraps PreTokenizedString
-pub struct PreTokenizedStream {
-    tokenized_string: PreTokenizedString,
-    current_token: i64,
-}
-
-impl From<PreTokenizedString> for PreTokenizedStream {
-    fn from(s: PreTokenizedString) -> PreTokenizedStream {
-        PreTokenizedStream {
-            tokenized_string: s,
-            current_token: -1,
-        }
-    }
-}
-
-impl PreTokenizedStream {
-    /// Creates a TokenStream from PreTokenizedString array
-    pub fn chain_tokenized_strings<'a>(
-        tok_strings: &'a [&'a PreTokenizedString],
-    ) -> Box<dyn TokenStream + 'a> {
-        if tok_strings.len() == 1 {
-            Box::new(PreTokenizedStream::from((*tok_strings[0]).clone()))
-        } else {
-            let mut offsets = vec![];
-            let mut total_offset = 0;
-            for &tok_string in tok_strings {
-                offsets.push(total_offset);
-                if let Some(last_token) = tok_string.tokens.last() {
-                    total_offset += last_token.offset_to;
-                }
-            }
-            let token_streams: Vec<_> = tok_strings
-                .iter()
-                .map(|tok_string| PreTokenizedStream::from((*tok_string).clone()))
-                .collect();
-            Box::new(TokenStreamChain::new(offsets, token_streams))
-        }
-    }
-}
-
-impl TokenStream for PreTokenizedStream {
-    fn advance(&mut self) -> bool {
-        self.current_token += 1;
-        self.current_token < self.tokenized_string.tokens.len() as i64
-    }
-
-    fn token(&self) -> &Token {
-        assert!(
-            self.current_token >= 0,
-            "TokenStream not initialized. You should call advance() at least once."
-        );
-        &self.tokenized_string.tokens[self.current_token as usize]
-    }
-
-    fn token_mut(&mut self) -> &mut Token {
-        assert!(
-            self.current_token >= 0,
-            "TokenStream not initialized. You should call advance() at least once."
-        );
-        &mut self.tokenized_string.tokens[self.current_token as usize]
-    }
-}
-
-#[cfg(test)]
-mod tests {
-
-    use super::*;
-
-    use crate::tokenizer::Token;
-
-    #[test]
-    fn test_tokenized_stream() {
-        let tok_text = PreTokenizedString {
-            text: String::from("A a"),
-            tokens: vec![
-                Token {
-                    offset_from: 0,
-                    offset_to: 1,
-                    position: 0,
-                    text: String::from("A"),
-                    position_length: 1,
-                },
-                Token {
-                    offset_from: 2,
-                    offset_to: 3,
-                    position: 1,
-                    text: String::from("a"),
-                    position_length: 1,
-                },
-            ],
-        };
-
-        let mut token_stream = PreTokenizedStream::from(tok_text.clone());
-
-        for expected_token in tok_text.tokens {
-            assert!(token_stream.advance());
-            assert_eq!(token_stream.token(), &expected_token);
-        }
-        assert!(!token_stream.advance());
-    }
-
-    #[test]
-    fn test_chain_tokenized_strings() {
-        let tok_text = PreTokenizedString {
-            text: String::from("A a"),
-            tokens: vec![
-                Token {
-                    offset_from: 0,
-                    offset_to: 1,
-                    position: 0,
-                    text: String::from("A"),
-                    position_length: 1,
-                },
-                Token {
-                    offset_from: 2,
-                    offset_to: 3,
-                    position: 1,
-                    text: String::from("a"),
-                    position_length: 1,
-                },
-            ],
-        };
-
-        let chain_parts = vec![&tok_text, &tok_text];
-
-        let mut token_stream = PreTokenizedStream::chain_tokenized_strings(&chain_parts[..]);
-
-        let expected_tokens = vec![
-            Token {
-                offset_from: 0,
-                offset_to: 1,
-                position: 0,
-                text: String::from("A"),
-                position_length: 1,
-            },
-            Token {
-                offset_from: 2,
-                offset_to: 3,
-                position: 1,
-                text: String::from("a"),
-                position_length: 1,
-            },
-            Token {
-                offset_from: 3,
-                offset_to: 4,
-                position: 3,
-                text: String::from("A"),
-                position_length: 1,
-            },
-            Token {
-                offset_from: 5,
-                offset_to: 6,
-                position: 4,
-                text: String::from("a"),
-                position_length: 1,
-            },
-        ];
-
-        for expected_token in expected_tokens {
-            assert!(token_stream.advance());
-            assert_eq!(token_stream.token(), &expected_token);
-        }
-        assert!(!token_stream.advance());
-    }
-}

src/tokenizer/tokenizer.rs

@@ -4,7 +4,7 @@ use crate::tokenizer::TokenStreamChain;
 use std::borrow::{Borrow, BorrowMut};
 
 /// Token
-#[derive(Debug, Clone, Serialize, Deserialize, Eq, PartialEq)]
+#[derive(Debug, Clone)]
 pub struct Token {
     /// Offset (byte index) of the first character of the token.
     /// Offsets shall not be modified by token filters.
@@ -58,10 +58,12 @@ pub trait Tokenizer<'a>: Sized + Clone {
     /// ```rust
     /// use tantivy::tokenizer::*;
     ///
+    /// # fn main() {
     /// let en_stem = SimpleTokenizer
     ///     .filter(RemoveLongFilter::limit(40))
     ///     .filter(LowerCaser)
     ///     .filter(Stemmer::default());
+    /// # }
     /// ```
     ///
     fn filter<NewFilter>(self, new_filter: NewFilter) -> ChainTokenizer<NewFilter, Self>
@@ -186,6 +188,7 @@ impl<'b> TokenStream for Box<dyn TokenStream + 'b> {
 /// ```
 /// use tantivy::tokenizer::*;
 ///
+/// # fn main() {
 /// let tokenizer = SimpleTokenizer
 ///        .filter(RemoveLongFilter::limit(40))
 ///        .filter(LowerCaser);
@@ -204,6 +207,7 @@ impl<'b> TokenStream for Box<dyn TokenStream + 'b> {
 ///     assert_eq!(token.offset_to, 12);
 ///     assert_eq!(token.position, 1);
 /// }
+/// # }
 /// ```
 ///
 pub trait TokenStream {
@@ -223,15 +227,17 @@ pub trait TokenStream {
     /// and `.token()`.
     ///
     /// ```
-    /// use tantivy::tokenizer::*;
-    ///
-    /// let tokenizer = SimpleTokenizer
-    ///       .filter(RemoveLongFilter::limit(40))
-    ///       .filter(LowerCaser);
+    /// # use tantivy::tokenizer::*;
+    /// #
+    /// # fn main() {
+    /// # let tokenizer = SimpleTokenizer
+    /// #       .filter(RemoveLongFilter::limit(40))
+    /// #       .filter(LowerCaser);
     /// let mut token_stream = tokenizer.token_stream("Hello, happy tax payer");
     /// while let Some(token) = token_stream.next() {
     ///     println!("Token {:?}", token.text);
     /// }
+    /// # }
     /// ```
     fn next(&mut self) -> Option<&Token> {
         if self.advance() {

tests/failpoints/mod.rs

@@ -1,8 +1,6 @@
 use fail;
 use std::path::Path;
-use tantivy::directory::{
-    Directory, ManagedDirectory, RAMDirectory, ReadOnlyDirectory, TerminatingWrite,
-};
+use tantivy::directory::{Directory, ManagedDirectory, RAMDirectory, TerminatingWrite};
 use tantivy::doc;
 use tantivy::schema::{Schema, TEXT};
 use tantivy::{Index, Term};
@@ -30,11 +28,11 @@ fn test_failpoints_managed_directory_gc_if_delete_fails() {
     // The initial 1*off is there to allow for the removal of the
     // lock file.
     fail::cfg("RAMDirectory::delete", "1*off->1*return").unwrap();
-    assert!(managed_directory.garbage_collect(Default::default).is_ok());
+    managed_directory.garbage_collect(Default::default);
     assert!(managed_directory.exists(test_path));
 
     // running the gc a second time should remove the file.
-    assert!(managed_directory.garbage_collect(Default::default).is_ok());
+    managed_directory.garbage_collect(Default::default);
     assert!(
         !managed_directory.exists(test_path),
         "The file should have been deleted"